USB: Gadget: fix UTF conversion in the usbstring library

This patch (as1234) fixes a bug in the UTF8 -> UTF-16 conversion
routine in the gadget/usbstring library.  In a UTF-8 multi-byte
sequence, all bytes after the first should have their high-order
two bits set to 10, not 11.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/usbstring.c

@@ -38,7 +38,7 @@ static int utf8_to_utf16le(const char *s, __le16 *cp, unsigned len)
 				uchar = (c & 0x1f) << 6;
 
 				c = (u8) *s++;
-				if ((c & 0xc0) != 0xc0)
+				if ((c & 0xc0) != 0x80)
 					goto fail;
 				c &= 0x3f;
 				uchar |= c;
@@ -49,13 +49,13 @@ static int utf8_to_utf16le(const char *s, __le16 *cp, unsigned len)
 				uchar = (c & 0x0f) << 12;
 
 				c = (u8) *s++;
-				if ((c & 0xc0) != 0xc0)
+				if ((c & 0xc0) != 0x80)
 					goto fail;
 				c &= 0x3f;
 				uchar |= c << 6;
 
 				c = (u8) *s++;
-				if ((c & 0xc0) != 0xc0)
+				if ((c & 0xc0) != 0x80)
 					goto fail;
 				c &= 0x3f;
 				uchar |= c;