rockchip: rk3368: spl: mark SPL and TPL as supported for ROCKCHIP_RK3368

With SPL and TPL support for the RK3368 in place, mark SPL and TPL as
supported from Kconfig for the RK3368.  As this is primarily tested on
the RK3368-uQ7, we'll leave it to board's individual defconfig to
enable.

Also enable DEBUG_UART_BOARD_INIT for the RK3368, so we get output
during the early boot-up, as we turn on TPL and SPL.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
index 8a89b51..b6f40d0 100644
--- a/arch/arm/mach-rockchip/Kconfig
+++ b/arch/arm/mach-rockchip/Kconfig
@@ -67,6 +67,13 @@
 config ROCKCHIP_RK3368
 	bool "Support Rockchip RK3368"
 	select ARM64
+	select SUPPORT_SPL
+	select SUPPORT_TPL
+	imply SPL_SEPARATE_BSS
+	imply SPL_SERIAL_SUPPORT
+	imply TPL_SERIAL_SUPPORT
+	select ENABLE_ARM_SOC_BOOT0_HOOK
+	select DEBUG_UART_BOARD_INIT
 	select SYS_NS16550
 	help
 	  The Rockchip RK3368 is a ARM-based SoC with a octa-core (organised