drm/tegra: Use standard GPL v2 license text

Use the more canonical and concise variant of the GPL v2 license text.
Acked-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NThierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/gr2d.c

 /*
  * Copyright (c) 2012-2013, NVIDIA Corporation.
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  */
 
 #include <linux/clk.h>