Convert CONFIG_SYS_OMAP_ABE_SYSCK to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_OMAP_ABE_SYSCK

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 78317e4..3bf9720 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -144,6 +144,9 @@
 	help
 	  Defines the MPU clock speed (in MHz).
 
+config SYS_OMAP_ABE_SYSCK
+	bool
+
 config TI_SECURE_EMIF_REGION_START
 	hex "Reserved EMIF region start address"
 	depends on TI_SECURE_DEVICE