ns16550: move CONFIG_SYS_NS16550 to Kconfig

Move CONFIG_SYS_NS16550 to Kconfig, and run moveconfig.py.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
diff --git a/configs/malta_defconfig b/configs/malta_defconfig
index 3056c48..2ebd58b 100644
--- a/configs/malta_defconfig
+++ b/configs/malta_defconfig
@@ -5,4 +5,5 @@
 # CONFIG_CMD_FPGA is not set
 # CONFIG_CMD_SETEXPR is not set
 # CONFIG_CMD_NFS is not set
+CONFIG_SYS_NS16550=y
 CONFIG_USE_PRIVATE_LIBGCC=y