clk: ti: Force pointer to be __iomem

Add __force here so that sparse doesn't complain about us playing
tricks with __iomem.

Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
diff --git a/drivers/clk/ti/clk.c b/drivers/clk/ti/clk.c
index 0d8861c..78a47cc 100644
--- a/drivers/clk/ti/clk.c
+++ b/drivers/clk/ti/clk.c
@@ -193,7 +193,7 @@
 
 	reg->offset = val;
 
-	return (void __iomem *)tmp;
+	return (__force void __iomem *)tmp;
 }
 
 /**