bochs: add page_flip
bochs: add page_flip

Implement crtc page_flip callback for bochsdrm.  The qemu stdvga has no
vblank signaling, so we have to fake it.  We do so by instantly calling
drm_send_vblank_event.  Tested with kmscon.

Signed-off-by: Gerd Hoffmann <cad73e70082427fddc9be3baaf34e698dffd21c0@redhat.com>
Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs