Instead of creating a dummy framebuffer allocation just so we can setup
crtc modes during display_setup we now wait until the first swap_buffers
request before setting up the crtc modes.
This patch also adds a cogl_kms_display_queue_modes_reset() function
that allows developers to explicitly queue a reset of the crtc modes.
The idea is that applications that handle VT switching can use this for
VT enter events to explicitly ensure their mode is restored since modes
are often not automatically restored correctly.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
