drivers/gpio/max730x.c: add license macro

According to the header in max730x it is licensed GPLv2.

Add a MODULE_LICENSE to avoid getting the kernel tainted.

[w.sang@pengutronix.de: add MODULE_AUTHOR and MODULE_DESCRIPTION also]
Signed-off-by: NRichard Röjfors <richard.rojfors@pelagicore.com>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/gpio/max730x.c

@@ -242,3 +242,7 @@ int __devexit __max730x_remove(struct device *dev)
 	return ret;
 }
 EXPORT_SYMBOL_GPL(__max730x_remove);
+
+MODULE_AUTHOR("Juergen Beisert, Wolfram Sang");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MAX730x GPIO-Expanders, generic parts");