ARM: sun6i: Define UART0 pins for A31

UART0 is the default debug/console UART on the A31.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
diff --git a/arch/arm/include/asm/arch-sunxi/gpio.h b/arch/arm/include/asm/arch-sunxi/gpio.h
index f7f3d8c..ba7e69b 100644
--- a/arch/arm/include/asm/arch-sunxi/gpio.h
+++ b/arch/arm/include/asm/arch-sunxi/gpio.h
@@ -132,6 +132,9 @@
 
 #define SUN4I_GPH22_SDC1	5
 
+#define SUN6I_GPH20_UART0_TX	2
+#define SUN6I_GPH21_UART0_RX	2
+
 #define SUN4I_GPI4_SDC3		2
 
 /* GPIO pin pull-up/down config */