ARM: rockchip: enable ZONE_DMA for non 64-bit capable peripherals

Most IP cores on ARM Rockchip platforms can only address 32 bits of
physical memory for DMA. Thus ZONE_DMA should be enabled when LPAE
is activated.
Signed-off-by: NTao Huang <huangtao@rock-chips.com>
Signed-off-by: NHeiko Stuebner <heiko@sntech.de>

arch/arm/mach-rockchip/Kconfig

@@ -16,6 +16,7 @@ config ARCH_ROCKCHIP
 	select ROCKCHIP_TIMER
 	select ARM_GLOBAL_TIMER
 	select CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
+	select ZONE_DMA if ARM_LPAE
 	help
 	  Support for Rockchip's Cortex-A9 Single-to-Quad-Core-SoCs
 	  containing the RK2928, RK30xx and RK31xx series.