regulator: rc5t583: Correct MODULE LICENSE to GPL v2

Fixing build issue reported by Paul Gortmaker:

It appears this breaks linux-next allmodconfig build, because it
uses an uppercase V in the v2 of its MODULE_LICENSE.

FATAL: modpost: GPL-incompatible module rc5t583-regulator.ko uses
GPL-only symbol 'platform_driver_unregister'
make[2]: *** [__modpost] Error 1
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/regulator/rc5t583-regulator.c

@@ -347,4 +347,4 @@ module_exit(rc5t583_regulator_exit);
 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 MODULE_DESCRIPTION("RC5T583 regulator driver");
 MODULE_ALIAS("platform:rc5t583-regulator");
-MODULE_LICENSE("GPL V2");
+MODULE_LICENSE("GPL v2");