ARM: pm: let platforms select cpu_suspend support

Support for the cpu_suspend functions is only built-in
when CONFIG_PM_SLEEP is enabled, but omap3/4, exynos4
and pxa always call cpu_suspend when CONFIG_PM is enabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 57b66d5..89bfb49 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -36,6 +36,7 @@
 	select ARM_L1_CACHE_SHIFT_6 if !ARCH_OMAP4
 	select ARCH_HAS_OPP
 	select PM_OPP if PM
+	select ARM_CPU_SUSPEND if PM
 
 config ARCH_OMAP4
 	bool "TI OMAP4"
@@ -50,6 +51,7 @@
 	select ARCH_HAS_OPP
 	select PM_OPP if PM
 	select USB_ARCH_HAS_EHCI
+	select ARM_CPU_SUSPEND if PM
 
 comment "OMAP Core Type"
 	depends on ARCH_OMAP2