ARM: BCM: Do not select CONFIG_MTD_NAND_BRCMNAND

This reverts 7dc95b40 ("ARM: BCM: Enable
NAND support for iProc SoCs") since it creates an unmet dependency for
MTD_NAND_BRCMNAND which depends on MTD and MTD_NAND, this results in the
following build failure for brcmnand:

 LD      init/built-in.o
drivers/built-in.o: In function `brcmnand_remove':
/home/fainelli/dev/linux/drivers/mtd/nand/brcmnand/brcmnand.c:2234:
undefined reference to `nand_release'
drivers/built-in.o: In function `brcmnand_init_cs':
/home/fainelli/dev/linux/drivers/mtd/nand/brcmnand/brcmnand.c:1933:
undefined reference to `nand_scan_ident'
/home/fainelli/dev/linux/drivers/mtd/nand/brcmnand/brcmnand.c:1958:
undefined reference to `nand_scan_tail'
Makefile:931: recipe for target 'vmlinux' failed
make: *** [vmlinux] Error 1

Instead, select this driver an all dependencies on the
multi_v7_defconfig.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>