Input: max11801_ts - correct license statement

The original license statement was confusing since it was unclear if
the license was pure GPLv2 or GPLv2+ and did not match the license
of the driver max11801_ts was derived from. The license is GPLv2+.
Signed-off-by: NJiejing Zhang <jiejing.zhang@freescale.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

drivers/input/touchscreen/max11801_ts.c

@@ -9,7 +9,8 @@
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License.
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
  */
 
 /*