LF-6806: dma: pxp: workaround for PXP when do RGB to gray color conversion

CSC2 engine in PXP has IC bug(TKT272216) and fixed after 7D PXP version.
Driver update new CSC coefficient provided by PXP IP owner(MLK-25625-02).
But when run e-ink case, it can't do clear operation after applying the
patch. We don't know reason until now, so add a temporary patch to fix it
and will remove after finding the root cause.

Signed-off-by: Guoniu.zhou <guoniu.zhou@nxp.com>
Reviewed-by: Robby Cai <robby.cai@nxp.com>