monitor/normal: Prefer modes with same flags as preferred mode

monitor/normal: Prefer modes with same flags as preferred mode

When generating MetaMonitorMode's, prefer CRTC modes that has the same
set of flags as the preferred mode. This not only is probably a better
set of configurable modes, but it'll guarantee that the preferred mode
is added.

This fixes a crash when the preferred mode was not the first mode with
the same resolution, refresh rate and set of handled modes.

https://bugzilla.gnome.org/show_bug.cgi?id=789153

Gbp-Pq: Name 0015-monitor-normal-Prefer-modes-with-same-flags.patch