Without this the compilation will fail, as the headers are installed in
a non-default location.
Signed-off-by: Emil Velikov <emil.velikov@collabora.com> Tested-by: Kai Wasserbäch <kai@dev.carbon-project.org> Reviewed-by: Kristian Høgsberg <krh@bitplanet.net> Reviewed-by: Matt Turner <mattst88@gmail.com>