USB: android: strim serial number buffer

User space writes USB serial number to a sysfs file.  Strim the
buffer before copying to USB string descriptor, otherwise
serial number may contain white spaces or new line characters.

Change-Id: If0dc699f53b92d80beaa099148f085d6c63af9a6
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
diff --git a/drivers/usb/gadget/android.c b/drivers/usb/gadget/android.c
index eefe95f..90a3b1e 100644
--- a/drivers/usb/gadget/android.c
+++ b/drivers/usb/gadget/android.c
@@ -1546,7 +1546,8 @@
 {									\
 	if (size >= sizeof(buffer))					\
 		return -EINVAL;						\
-	return strlcpy(buffer, buf, sizeof(buffer));			\
+	strlcpy(buffer, strim((char *) buf), sizeof(buffer));		\
+	return size;							\
 }									\
 static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, field ## _show, field ## _store);