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/qemu-x86_defconfig b/configs/qemu-x86_defconfig
index 366ccc4..92e79de 100644
--- a/configs/qemu-x86_defconfig
+++ b/configs/qemu-x86_defconfig
@@ -19,6 +19,7 @@
 CONFIG_E1000=y
 CONFIG_DM_PCI=y
 CONFIG_DM_RTC=y
+CONFIG_SYS_NS16550=y
 CONFIG_USB=y
 CONFIG_DM_USB=y
 CONFIG_VIDEO_VESA=y