Revert "gbm: work around mesa linkage issue"
Revert "gbm: work around mesa linkage issue"

This reverts commit 9a4f7c0e4b50f1053318cc76478da530b7b66299.

Remove this ugly workaround. Fixed versions of Mesa have been deployed
5+ years ago.

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>

Conflicts:
	src/waffle/gbm/wgbm_display.c

waffle-gl/waffle,waffle-gl/waffle,waffle-gl/waffle,waffle-gl/waffle