native/gpu: Handle drmModeSetCrtc() failing gracefully

native/gpu: Handle drmModeSetCrtc() failing gracefully

If drmModeSetCrtc() is called with no fb, mode or connectors for some
CRTC it may still fail, and we should handle that gracefully instead of
assuming it failed to set a non-disabled state.

Closes https://gitlab.gnome.org/GNOME/mutter/issues/70

(cherry picked from commit 6e953e2725d5d5b10d14c7bd479bd99f6853addc)

Bug-GNOME: https://gitlab.gnome.org/GNOME/mutter/issues/70
Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1754949
Applied-Upstream: https://gitlab.gnome.org/GNOME/mutter/commit/44682a2cc555

Gbp-Pq: Name native-gpu-Handle-drmModeSetCrtc-failing-gracefully.patch