[Buildroot] [git commit branch/2022.05.x] Revert "configs/olimex_a20_olinuxino_lime2: use NEON+VFPv4 as FPU strategy"

[Buildroot] [git commit branch/2022.05.x] Revert "configs/olimex_a20_olinuxino_lime2: use NEON+VFPv4 as FPU strategy"

[Peter Korsgaard]

commit: https://git.buildroot.net/buildroot/commit/?id=7cb55f80987a869d8259197ee59043791cdb33b7
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/2022.05.x

The gcc man page states that specifying Neon as part of the fpu setting
has no effect, unless the -funsafe-math-optimizations is also specified,
because Neon is not compliant with IEEE 754:
```
    If the selected floating-point hardware includes the NEON extension
    (e.g. -mfpu=neon), note that floating-point operations are not
    generated by GCC's auto-vectorization pass unless
    -funsafe-math-optimizations is also specified. This is because NEON
    hardware does not fully implement the IEEE 754 standard for
    floating-point arithmetic (in particular denormal values are treated
    as zero), so the use of NEON instructions may lead to a loss of
    precision.
```

-funsafe-math-optimizations must be explictly specified per package to
really use NEON as FPU, but it's something that is left to the user as
well as setting BR2_ARM_FPU_NEON_VFPV4. This way the default
BR2_ARM_FPU_VFPV4D16 is used as previously. So let's revert the
offending patch.

This reverts commit f8528acdfda278ea9f2f9bc8a47eb77ace0c050f.

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit 869fe1fbab7f769007995356e7cf15a9df6b28b5)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
---
 configs/olimex_a20_olinuxino_lime2_defconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/configs/olimex_a20_olinuxino_lime2_defconfig b/configs/olimex_a20_olinuxino_lime2_defconfig
index 2f95949214..2e92f5740c 100644
--- a/configs/olimex_a20_olinuxino_lime2_defconfig
+++ b/configs/olimex_a20_olinuxino_lime2_defconfig
@@ -2,7 +2,6 @@
 BR2_arm=y
 BR2_cortex_a7=y
 BR2_ARM_EABIHF=y
-BR2_ARM_FPU_NEON_VFPV4=y
 
 # Linux headers same as kernel, a 5.15 LTS series
 BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_5_15=y
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