Staging: fbtft: Remove paragraph about writing to FSF

Remove paragraph about writing to the Free Software Foundation's
mailing address from GPL notice.
This patch fixes the following checkpatch error:

CHECK:FSF_MAILING_ADDRESS at line 17.
Signed-off-by: Fabio Falzoi <fabio.falzoi84@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fbtft/flexfb.c

@@ -12,10 +12,6 @@
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
 #include <linux/module.h>