ARM: 6962/1: mach-h720x: fix build error

The h7201/h7202 machines did not build since they define
ARM_DMA_ZONE_OFFSET but do not select ZONE_DMA. Fix it up by
selecting ZONE_DMA in their Kconfig.

Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-h720x/Kconfig

@@ -6,12 +6,14 @@ config ARCH_H7201
 	bool "gms30c7201"
 	depends on ARCH_H720X
 	select CPU_H7201
+	select ZONE_DMA
 	help
 	  Say Y here if you are using the Hynix GMS30C7201 Reference Board
 
 config ARCH_H7202
 	bool "hms30c7202"
 	select CPU_H7202
+	select ZONE_DMA
 	depends on ARCH_H720X
 	help
 	  Say Y here if you are using the Hynix HMS30C7202 Reference Board