ARM: ep93xx: switch to GENERIC_CLOCKEVENTS

This switches the EP93xx to use GENERIC_CLOCKEVENTS and
CLKSRC_MMIO. Also implements a sched_clock() hook.
Tested on the SIM.ONE. Use only oneshot events.

Tested-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a750c14..00623a2 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -418,11 +418,12 @@
 	bool "EP93xx-based"
 	select ARCH_HAS_HOLES_MEMORYMODEL
 	select ARCH_REQUIRE_GPIOLIB
-	select ARCH_USES_GETTIMEOFFSET
 	select ARM_AMBA
 	select ARM_VIC
 	select CLKDEV_LOOKUP
+	select CLKSRC_MMIO
 	select CPU_ARM920T
+	select GENERIC_CLOCKEVENTS
 	help
 	  This enables support for the Cirrus EP93xx series of CPUs.