mfd: tpx6586x: Depend on regulator

Some of the OF binding stuff is done in the MFD.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/mfd/Kconfig

@@ -162,6 +162,7 @@ config MFD_TPS6586X
 	bool "TPS6586x Power Management chips"
 	depends on I2C=y && GPIOLIB && GENERIC_HARDIRQS
 	select MFD_CORE
+	depends on REGULATOR
 	help
 	  If you say yes here you get support for the TPS6586X series of
 	  Power Management chips.