build: add build-time check for gbm_bo_get_stride()

build: add build-time check for gbm_bo_get_stride()

Upstream mesa renamed gbm_bo_get_pitch() to gbm_bo_get_stride(). As gbm
has not seen an official release, they actually don't care but several
users complained about this. Therefore, we simply add a build-time check
for this. However, this may break when mesa is updated without recompiling
kmscon but that is less intrusive.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>