panfrost: Don't use AFBC of sRGB luminance-alpha
This isn't allowed for the same reason that AFBC of regular luminance-alpha isn't allowed (and will raise DATA_INVALID_FAULTs). Reorder the checks to ensure these formats are checked.
Fixes Piglit texwrap GL_EXT_texture_sRGB-s3tc.
Fixes: 476be5cb ("panfrost: Don't use texture format swizzles on v7") Signed-off-by: Alyssa Rosenzweig alyssa@collabora.com