allwinner: Use RSB for the PMIC connection on H6

RSB is faster and more efficient, and it has a simpler driver. As long
as the PMIC is returned to I2C mode after use, the rich OS can later use
either bus.

Change-Id: I0c5f32e88a090c8c5cccb81bd24596b301ab9da7
Signed-off-by: Samuel Holland <samuel@sholland.org>
diff --git a/plat/allwinner/sun50i_h6/include/sunxi_mmap.h b/plat/allwinner/sun50i_h6/include/sunxi_mmap.h
index 702db77..1b71606 100644
--- a/plat/allwinner/sun50i_h6/include/sunxi_mmap.h
+++ b/plat/allwinner/sun50i_h6/include/sunxi_mmap.h
@@ -55,6 +55,7 @@
 #define SUNXI_R_TWD_BASE		0x07020800
 #define SUNXI_R_CPUCFG_BASE		0x07000400
 #define SUNXI_R_I2C_BASE		0x07081400
+#define SUNXI_R_RSB_BASE		0x07083000
 #define SUNXI_R_UART_BASE		0x07080000
 #define SUNXI_R_PIO_BASE		0x07022000