spi: fsl-lpspi: use GPL as module license

At the beginning of lpspi driver, it is claimed that the dirver
is under the terms of the GNU General Public License, either
version 2 of the License. While at the end I only declared GPL V2.

This patch make the license consistent.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-fsl-lpspi.c

@@ -519,4 +519,4 @@ module_platform_driver(fsl_lpspi_driver);
 
 MODULE_DESCRIPTION("LPSPI Master Controller driver");
 MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
-MODULE_LICENSE("GPL v2");
+MODULE_LICENSE("GPL");