drm/msm/a6xx: Fix excessive stack usage

drm/msm/a6xx: Fix excessive stack usage

Clang-19 and above sometimes end up with multiple copies of the large
a6xx_hfi_msg_bw_table structure on the stack. The problem is that
a6xx_hfi_send_bw_table() calls a number of device specific functions to
fill the structure, but these create another copy of the structure on
the stack which gets copied to the first.

If the functions get inlined, that busts the warning limit:

drivers/gpu/drm/msm/adreno/a6xx_hfi.c:631:12: error: stack frame size (1032) exceeds limit (1024) in 'a6xx_hfi_send_bw_table' [-Werror,-Wframe-larger-than]

Fix this by kmalloc-ating struct a6xx_hfi_msg_bw_table instead of using
the stack. Also, use this opportunity to skip re-initializing this table
to optimize gpu wake up latency.

Cc: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/621814/
Signed-off-by: Rob Clark <robdclark@chromium.org>