Input: docs - remove disclaimer/GPL notice

This is just a part of kernel documentation, it does not require explicit
license notice.

Signed-off-by: Dmitry Torokhov <[e-mail]>

Documentation/input/index.rst

···
 The Linux Input Documentation
 =============================
 
-Disclaimer
-==========
-
-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, or (at your option)
-any later version.
-
-This program is distributed in the hope that it will be useful, 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., 59
-Temple Place, Suite 330, Boston, MA 02111-1307 USA
-
-For your convenience, the GNU General Public License version 2 is included
-in the package: See the file COPYING.
-
-
 Core API
 ========