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/igep0030_nand_defconfig b/configs/igep0030_nand_defconfig
index 54f1ff8..dce7e06 100644
--- a/configs/igep0030_nand_defconfig
+++ b/configs/igep0030_nand_defconfig
@@ -7,3 +7,4 @@
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_GPIO=y
 # CONFIG_CMD_SETEXPR is not set
+CONFIG_SYS_NS16550=y