Add detection of Nuvoton WPCM450.

Signed-off-by: Zheng Bao <zheng.bao@amd.com>

Index: util/superiotool/nuvoton.c
===================================================================
--- util/superiotool/nuvoton.c	(revision 6221)
+++ util/superiotool/nuvoton.c	(working copy)
@@ -64,6 +64,8 @@
 			{0x30,0x60,0x61,0x70,0x71,0x74,0x75,0xf0,EOT},
 			{0x00,0x02,0xf8,0x03,0x03,0x04,0x04,0x02,EOT}},
 		{EOT}}},
+	{0x1a, "WPCM450", {
+		{EOT}}},
 	{EOT}
 };