rockchip: Enable pre console for rk3399

Enable pre console buffer for rk3399 platform.

This would help to capture the console messages prior to
the console being initialised. Enabling this would help
to capture all the console messages on video output source
like HDMI. So we can find the full console messages of
U-Boot proper on HDMI display when enabled it for RK3399
platform boards.

Buffer address used for pre console is 0x0f200000 which is
ram base plus 240MiB. right now the Allwinner SoC is using
similar computation.
Signed-off-by: NJagan Teki <jagan@amarulasolutions.com>
Reviewed-by: NKever Yang <kever.yang@rock-chips.com>
Tested-by: NPeter Robinson <pbrobinson@gmail.com>

arch/arm/mach-rockchip/Kconfig

@@ -229,6 +229,7 @@ config ROCKCHIP_RK3399
 	select DM_PMIC
 	select DM_REGULATOR_FIXED
 	select BOARD_LATE_INIT
+	imply PRE_CONSOLE_BUFFER
 	imply ROCKCHIP_COMMON_BOARD
 	imply ROCKCHIP_SDRAM_COMMON
 	imply SPL_ROCKCHIP_COMMON_BOARD

common/Kconfig

@@ -568,6 +568,7 @@ config PRE_CON_BUF_ADDR
 	default 0x2f000000 if ARCH_SUNXI && MACH_SUN9I
 	default 0x4f000000 if ARCH_SUNXI && !MACH_SUN9I
 	default 0x0f000000 if ROCKCHIP_RK3288
+	default 0x0f200000 if ROCKCHIP_RK3399
 	help
 	  This sets the start address of the pre-console buffer. This must
 	  be in available memory and is accessed before relocation and