ARM: Orion: XOR: Add support for clk

Some orion platforms can gate the XOR driver clock. If the clock
exisits, unable/disable it as appropriate.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Jamie Lentin <jm@lentin.co.uk>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/dma/mv_xor.h b/drivers/dma/mv_xor.h
index 654876b..a5b422f 100644
--- a/drivers/dma/mv_xor.h
+++ b/drivers/dma/mv_xor.h
@@ -55,6 +55,7 @@
 struct mv_xor_shared_private {
 	void __iomem	*xor_base;
 	void __iomem	*xor_high_base;
+	struct clk	*clk;
 };