ARM: OMAP2+: add missing ARCH_HAS_OPP

OMAP5, DRA7, AM43xx all have OPPs. So select the same to allow SoC
only configuration boot to work with OPP.
Reported-by: Nikhil Devshatwar <nikhil.nd@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/Kconfig

@@ -50,6 +50,7 @@ config SOC_OMAP5
 	bool "TI OMAP5"
 	depends on ARCH_MULTI_V7
 	select ARCH_OMAP2PLUS
+	select ARCH_HAS_OPP
 	select ARM_CPU_SUSPEND if PM
 	select ARM_GIC
 	select CPU_V7
@@ -63,6 +64,7 @@ config SOC_AM33XX
 	bool "TI AM33XX"
 	depends on ARCH_MULTI_V7
 	select ARCH_OMAP2PLUS
+	select ARCH_HAS_OPP
 	select ARM_CPU_SUSPEND if PM
 	select CPU_V7
 	select MULTI_IRQ_HANDLER
@@ -72,6 +74,7 @@ config SOC_AM43XX
 	depends on ARCH_MULTI_V7
 	select CPU_V7
 	select ARCH_OMAP2PLUS
+	select ARCH_HAS_OPP
 	select MULTI_IRQ_HANDLER
 	select ARM_GIC
 	select MACH_OMAP_GENERIC
@@ -80,6 +83,7 @@ config SOC_DRA7XX
 	bool "TI DRA7XX"
 	depends on ARCH_MULTI_V7
 	select ARCH_OMAP2PLUS
+	select ARCH_HAS_OPP
 	select ARM_CPU_SUSPEND if PM
 	select ARM_GIC
 	select CPU_V7