MX6: fix sata compilation for i.MX6

Commit 164d98466103a46b7c881149e92ec2a28a6375be breaks
board with SATA support, because sata is not compiled.

Signed-off-by: Stefano Babic <sbabic@denx.de>
diff --git a/arch/arm/imx-common/sata.c b/arch/arm/imx-common/sata.c
index 1b4c502..2e69486 100644
--- a/arch/arm/imx-common/sata.c
+++ b/arch/arm/imx-common/sata.c
@@ -7,6 +7,7 @@
 #include <asm/imx-common/iomux-v3.h>
 #include <asm/arch/iomux.h>
 #include <asm/io.h>
+#include <asm/arch/clock.h>
 
 int setup_sata(void)
 {