fpga: use SPDX

Replace GPLv2 boilerplate with SPDX in FPGA code that came from me or
from Altera.

Signed-off-by: Alan Tull <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
diff --git a/drivers/fpga/altera-fpga2sdram.c b/drivers/fpga/altera-fpga2sdram.c
index 5a29ab6..23660ccd 100644
--- a/drivers/fpga/altera-fpga2sdram.c
+++ b/drivers/fpga/altera-fpga2sdram.c
@@ -1,19 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * FPGA to SDRAM Bridge Driver for Altera SoCFPGA Devices
  *
  *  Copyright (C) 2013-2016 Altera Corporation, All Rights Reserved.
- *
- * 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/>.
  */
 
 /*