radv: align pipeline cache entry and header sizes

Fixes UBSan error:
../src/amd/vulkan/radv_pipeline_cache.c:603:42: runtime error: member access within misaligned address 0x00000152ebcc for type 'struct cache_entry', which requires 8 byte alignment

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6206>
1 file changed