Fix the issue of usb_kbd driver missing the scan code of key 'z'.

The scan code of the key 'z' is 0x1d, which should be handled.

The change has be tested on NOVATEK USB keyboard and ULI PCI OHCI
controller.

Signed-off-by: Zhang Wei <wei.zhang@freescale.com>
Signed-off-by: Markus Klotzbuecher <mk@denx.de>
diff --git a/common/usb_kbd.c b/common/usb_kbd.c
index aec558a..7bdfcc0 100644
--- a/common/usb_kbd.c
+++ b/common/usb_kbd.c
@@ -257,7 +257,7 @@
 		repeat_delay=REPEAT_DELAY;
 	}
 	keycode=0;
-	if((scancode>3) && (scancode<0x1d)) { /* alpha numeric values */
+	if((scancode>3) && (scancode<=0x1d)) { /* alpha numeric values */
 		keycode=scancode-4 + 0x61;
 		if(caps_lock)
 			keycode&=~CAPITAL_MASK; /* switch to capital Letters */