This helps when e.g. changing the resolution on the Dell Latitude D531,
which reports that it supports large resolutions (e.g. 1920x1440x32 and
others larger than 1024x768x32) but fails to apply these.
This usually happens because PDEVOBJ_pSurface(), and more precisely
ppdev->pldev->pfn.EnableSurface(), fails for these resolutions.
- PDEVOBJ_bSwitchMode(): Set the new video mode, or restore the original
one in case of failure + release the allocated ppdevTmp if previous
calls fail. Also unlock in reverse order of locking order.
- UserChangeDisplaySettings(): In case PDEVOBJ_pSurface() fails (but has
reverted the original video mode), we still need to refresh the
display since the display may have been messed up.