modesetting: Do not fail if glamor fails.

If glamor initialization fails, we can still use the good old fb code.

Downgrade the glamor initialization error as a warning and move on.

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Closes: xorg/xserver#99
4 jobs for modesetting-no-glamor in 5 minutes and 5 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Docker Image
passed #7222927
debian-buster

00:00:21

 
  Build And Test
passed #7222928
autotools

00:04:43

passed #7222929
meson

00:01:49

passed #7222930
meson-noglamor

00:01:34