We're using the former only as the latter is present. Thus in some cases
we might incorrectly error out if it's missing.
Namely - glamor_glx, glamor_egl without gbm, EGL_KHR_gl_texture_2D_image
or EGL_EXT_image_dma_buf_import.
Fixes 58d54ee82df(glamor: explicitly check for GL_OES_EGL_image)
Cc: Eric Anholt <eric@anholt.net>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Suggested-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>