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/Mele_I7_defconfig b/configs/Mele_I7_defconfig
index bfe2a29..bed8afb 100644
--- a/configs/Mele_I7_defconfig
+++ b/configs/Mele_I7_defconfig
@@ -17,4 +17,5 @@
 CONFIG_AXP_ALDO1_VOLT=3300
 CONFIG_AXP_DLDO1_VOLT=3300
 CONFIG_AXP_DLDO4_VOLT=3300
+CONFIG_SYS_NS16550=y
 CONFIG_USB_EHCI_HCD=y