serial: uartlite: Move driver to DM

Enable SPL DM too.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Thomas Chou <thomas@wytron.com.tw>
diff --git a/configs/microblaze-generic_defconfig b/configs/microblaze-generic_defconfig
index ed336e6..6b038b8 100644
--- a/configs/microblaze-generic_defconfig
+++ b/configs/microblaze-generic_defconfig
@@ -1,5 +1,6 @@
 CONFIG_MICROBLAZE=y
 CONFIG_SPL_SYS_MALLOC_SIMPLE=y
+CONFIG_SPL_DM=y
 CONFIG_TARGET_MICROBLAZE_GENERIC=y
 CONFIG_SYS_TEXT_BASE=0x29000000
 CONFIG_DEFAULT_DEVICE_TREE="microblaze-generic"
@@ -7,4 +8,5 @@
 CONFIG_SYS_PROMPT="U-Boot-mONStR> "
 CONFIG_CMD_GPIO=y
 # CONFIG_CMD_SETEXPR is not set
+CONFIG_SPL_OF_CONTROL=y
 CONFIG_OF_EMBED=y