mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver

mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver

This is based on Linux kernel -next:

commit 14f44abf1dafc20ba42ce8616a8fc8fbd1b3712b
Author: Brian Norris <computersforpeace@gmail.com>
Date:   Fri Jul 13 09:28:24 2012 -0700

    mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver

    The NAND_CHIPOPTIONS_MSK has limited utility and is causing real bugs. It
    silently masks off at least one flag that might be set by the driver
    (NAND_NO_SUBPAGE_WRITE). This breaks the GPMI NAND driver and possibly
    others.

    Really, as long as driver writers exercise a small amount of care with
    NAND_* options, this mask is not necessary at all; it was only here to
    prevent certain options from accidentally being set by the driver. But the
    original thought turns out to be a bad idea occasionally. Thus, kill it.

    Note, this patch fixes some major gpmi-nand breakage.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Eric Nelson <eric.nelson@boundarydevices.com>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>