[PATCH] drm/i915/guc, docs: Fix pdfdocs build error by removing nested grid

[Akira Yokosawa <akiyks@gmail.com>]

Nested grids in grid-table cells are not specified as proper ReST
constructs.
Commit 572f2a5cd974 ("drm/i915/guc: Update firmware to v62.0.0")
added a couple of kerneldoc tables of the form:

  +---+-------+------------------------------------------------------+
  | 1 |  31:0 |  +------------------------------------------------+  |
  +---+-------+  |                                                |  |
  |...|       |  |  Embedded `HXG Message`_                       |  |
  +---+-------+  |                                                |  |
  | n |  31:0 |  +------------------------------------------------+  |
  +---+-------+------------------------------------------------------+

For "make htmldocs", they happen to work as one might expect,
but they are incompatible with "make latexdocs" and "make pdfdocs",
and cause the generated gpu.tex file to become incomplete and
unbuildable by xelatex.

Restore the compatibility by removing those nested grids in the tables.

Size comparison of generated gpu.tex:

                  Sphinx 2.4.4  Sphinx 4.2.0
  v5.14:               3238686       3841631
  v5.15-rc1:            376270        432729
  with this fix:       3377846       3998095

Fixes: 572f2a5cd974 ("drm/i915/guc: Update firmware to v62.0.0")
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
---
Hi all,

I know there is little interest in building pdfdocs (or LaTeX) version
of kernel-doc, and this issue does not matter most of you.

But "make pdfdocs" is supposed to work, give or take those tables
with squeezed columns, and at least it is expected to complete
without fatal errors.

I have no idea who is responsible to those grid-tables, so added
a lot of people in the To: and Cc: lists.

Does removing those nested grids look reasonable to you?

Any feedback is welcome!

Note: This patch is against the docs-next branch of Jon's -doc tree
(git://git.lwn.net/linux.git).  It can be applied against v5.15-rc1
and v5.15-rc2 as well.

        Thanks, Akira
--
 .../gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h | 10 +++++-----
 .../drm/i915/gt/uc/abi/guc_communication_mmio_abi.h    | 10 +++++-----
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h b/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h
index 99e1fad5ca20..c9086a600bce 100644
--- a/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h
+++ b/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h
@@ -102,11 +102,11 @@ static_assert(sizeof(struct guc_ct_buffer_desc) == 64);
  *  |   +-------+--------------------------------------------------------------+
  *  |   |   7:0 | NUM_DWORDS = length (in dwords) of the embedded HXG message  |
  *  +---+-------+--------------------------------------------------------------+
- *  | 1 |  31:0 |  +--------------------------------------------------------+  |
- *  +---+-------+  |                                                        |  |
- *  |...|       |  |  Embedded `HXG Message`_                               |  |
- *  +---+-------+  |                                                        |  |
- *  | n |  31:0 |  +--------------------------------------------------------+  |
+ *  | 1 |  31:0 |                                                              |
+ *  +---+-------+                                                              |
+ *  |...|       | [Embedded `HXG Message`_]                                    |
+ *  +---+-------+                                                              |
+ *  | n |  31:0 |                                                              |
  *  +---+-------+--------------------------------------------------------------+
  */
 
diff --git a/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_mmio_abi.h b/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_mmio_abi.h
index bbf1ddb77434..9baa3cb07d13 100644
--- a/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_mmio_abi.h
+++ b/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_mmio_abi.h
@@ -38,11 +38,11 @@
  *  +---+-------+--------------------------------------------------------------+
  *  |   | Bits  | Description                                                  |
  *  +===+=======+==============================================================+
- *  | 0 |  31:0 |  +--------------------------------------------------------+  |
- *  +---+-------+  |                                                        |  |
- *  |...|       |  |  Embedded `HXG Message`_                               |  |
- *  +---+-------+  |                                                        |  |
- *  | n |  31:0 |  +--------------------------------------------------------+  |
+ *  | 0 |  31:0 |                                                              |
+ *  +---+-------+                                                              |
+ *  |...|       | [Embedded `HXG Message`_]                                    |
+ *  +---+-------+                                                              |
+ *  | n |  31:0 |                                                              |
  *  +---+-------+--------------------------------------------------------------+
  */
 

base-commit: 242f4c77b1c8cebfdfa0ad5b40e2e4ae0316e57d
-- 
2.17.1