MLK-19152-2 drm/imx: lcdif: force 'mode_changed' when fb width changed

MLK-19152-2 drm/imx: lcdif: force 'mode_changed' when fb width changed

In DRM atomic modeset check, it will not check the fb's width
change, so in later atomic commit, it will not disable the CRTC
which has no mode changed. But for LCDIF, the fb width related
registers configuration can not be done when LCDIF is running.
So force 'mode_changed' to be true when fb width changed.

Signed-off-by: Fancy Fang <chen.fang@nxp.com>
(cherry picked from commit 518ff82756a39ff2d2f750596295baa4f5fca4c5)
(cherry picked from commit c399d83491cb80ca9d6b040cdf3e9d1e709785b2)