mfd: stmpe-i2c: Add missing MODULE_LICENSE

This driver is licensed GPL-2.0-only, so add the corresponding module flag.

Signed-off-by: Alexander Stein <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Lee Jones <[e-mail]>

drivers/mfd/stmpe-i2c.c

···
 
 MODULE_DESCRIPTION("STMPE MFD I2C Interface Driver");
 MODULE_AUTHOR("Rabin Vincent <[e-mail]>");
+MODULE_LICENSE("GPL");