st/mesa: Fall back to R8G8B8A8_SRGB for ETC2
If the driver doesn't support PIPE_FORMAT_B8G8R8A8_SRGB, fall back to PIPE_FORMAT_R8G8B8A8_SRGB. Drivers such as Virgl will have a hard time supporting PIPE_FORMAT_B8G8R8A8_SRGB when the host runs GLES, as GL_BGRA isn't as well suported there. So go with PIPE_FORMAT_R8G8B8A8_SRGB so these drivers can avoid a conversion copy. v2: Fix typo in commit message Signed-off-by:Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by:
Marek Olšák <marek.olsak@amd.com>