ARM: OMAP5: add CKO buffer control mask

Add CKOBUFFER_CLK_EN bit mask enabling FREF_XTAL_CLK clock.

Signed-off-by: Dmitry Lifshitz <lifshitz@compulab.co.il>
diff --git a/arch/arm/include/asm/arch-omap5/clock.h b/arch/arm/include/asm/arch-omap5/clock.h
index 2dfe4ef..30d9de2 100644
--- a/arch/arm/include/asm/arch-omap5/clock.h
+++ b/arch/arm/include/asm/arch-omap5/clock.h
@@ -322,6 +322,9 @@
 
 #define V_SCLK	V_OSCK
 
+/* CKO buffer control */
+#define CKOBUFFER_CLK_ENABLE_MASK	(1 << 28)
+
 /* AUXCLKx reg fields */
 #define AUXCLK_ENABLE_MASK		(1 << 8)
 #define AUXCLK_SRCSELECT_SHIFT		1