rockchip: Use the debug UART on rk3036

Rather than using a new debug UART implementation, use the standard one
provided by U-Boot.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Thomas Chou <thomas@wytron.com.tw>
diff --git a/configs/evb-rk3036_defconfig b/configs/evb-rk3036_defconfig
index 2e915ff..c196bd6 100644
--- a/configs/evb-rk3036_defconfig
+++ b/configs/evb-rk3036_defconfig
@@ -24,3 +24,9 @@
 CONFIG_USE_PRIVATE_LIBGCC=y
 CONFIG_CMD_DHRYSTONE=y
 CONFIG_ERRNO_STR=y
+CONFIG_DEBUG_UART=y
+CONFIG_DEBUG_UART_NS16550=y
+CONFIG_DEBUG_UART_BASE=0x20068000
+CONFIG_DEBUG_UART_CLOCK=24000000
+CONFIG_DEBUG_UART_SHIFT=2
+# CONFIG_SPL_SERIAL_PRESENT is not set