modesetting: unflip not possible when glamor is not set

This is fixing crashes of xfce when running under qemu
6 jobs for issue1195_fix in 7 minutes and 19 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Docker Image
passed debian-buster #12058442

00:00:11

 
  Build And Test
passed autotools #12058449

00:04:46

passed meson #12058444

00:02:12

passed meson-noglamor #12058445

00:01:33

passed mingw-cross-build #12058446

00:00:40

canceled autotools #12058443

00:03:00