ARM: ux500: Enable Kconfig for the generic PM domain

Since ux500 uses the generic PM domain, let's enable the corresponding
Kconfig as long as CONFIG_PM also is enabled.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/mach-ux500/Kconfig

@@ -32,6 +32,7 @@ config UX500_SOC_DB8500
 	select PINCTRL_AB8540
 	select REGULATOR
 	select REGULATOR_DB8500_PRCMU
+	select PM_GENERIC_DOMAINS if PM
 
 config MACH_MOP500
 	bool "U8500 Development platform, MOP500 versions"