[PATCH v2 2/3] drm/i915: Fix header test for !CONFIG_X86

[Lucas De Marchi <lucas.demarchi@intel.com>]

Architectures others than x86 have a stub implementation calling
WARN_ON_ONCE(). The appropriate headers need to be included, otherwise
the header-test target will fail with:

  HDRTEST drivers/gpu/drm/i915/i915_mm.h
In file included from <command-line>:
./drivers/gpu/drm/i915/i915_mm.h: In function ‘remap_io_mapping’:
./drivers/gpu/drm/i915/i915_mm.h:26:2: error: implicit declaration of function ‘WARN_ON_ONCE’ [-Werror=implicit-function-declaration]
   26 |  WARN_ON_ONCE(1);
      |  ^~~~~~~~~~~~

v2: Do not include <linux/printk.h> since call to pr_err() has been
removed

Fixes: 67c430bbaae1 ("drm/i915: Skip remap_io_mapping() for non-x86 platforms")
Cc: Siva Mullati <siva.mullati@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
---
 drivers/gpu/drm/i915/i915_mm.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/i915_mm.h b/drivers/gpu/drm/i915/i915_mm.h
index 76f1d53bdf34..3ad22bbe80eb 100644
--- a/drivers/gpu/drm/i915/i915_mm.h
+++ b/drivers/gpu/drm/i915/i915_mm.h
@@ -6,6 +6,7 @@
 #ifndef __I915_MM_H__
 #define __I915_MM_H__
 
+#include <linux/bug.h>
 #include <linux/types.h>
 
 struct vm_area_struct;
-- 
2.35.0