ARM: imx: gpmi-nand depends on mxs-dma

It is not currently possible to build the gpmi-nand driver without
also building the mxs-dma driver. Clarify this Kconfig and enable
both in the defconfig file so we can build it again with both enabled.

drivers/built-in.o: In function `gpmi_dma_filter':
clk-fixed-factor.c:(.text+0xafc18): undefined reference to `mxs_dma_is_apbh'
make[1]: *** [vmlinux] Error 1
make: *** [sub-make] Error 2

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <kernel@pengutronix.de>

arch/arm/configs/imx_v6_v7_defconfig

@@ -192,6 +192,7 @@ CONFIG_RTC_DRV_MC13XXX=y
 CONFIG_RTC_DRV_MXC=y
 CONFIG_DMADEVICES=y
 CONFIG_IMX_SDMA=y
+CONFIG_MXS_DMA=y
 CONFIG_COMMON_CLK_DEBUG=y
 # CONFIG_IOMMU_SUPPORT is not set
 CONFIG_EXT2_FS=y

drivers/mtd/nand/Kconfig

@@ -480,7 +480,7 @@ config MTD_NAND_NANDSIM
 
 config MTD_NAND_GPMI_NAND
         bool "GPMI NAND Flash Controller driver"
-        depends on MTD_NAND && (SOC_IMX23 || SOC_IMX28 || SOC_IMX6Q)
+        depends on MTD_NAND && MXS_DMA
         help
 	 Enables NAND Flash support for IMX23 or IMX28.
 	 The GPMI controller is very powerful, with the help of BCH