mfd: Fix build breakage caused by tps65910 gpio directory move

Signed-off-by: NLiam Girdwood <lrg@ti.com>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

drivers/mfd/Kconfig

@@ -721,7 +721,7 @@ config MFD_PM8XXX_IRQ
 
 config MFD_TPS65910
 	bool "TPS65910 Power Management chip"
-	depends on I2C=y
+	depends on I2C=y && GPIOLIB
 	select MFD_CORE
 	select GPIO_TPS65910
 	help