common: Drop log.h from common header

Move this header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-imx/mx6/clock.c b/arch/arm/mach-imx/mx6/clock.c
index 9f3d62f..fb5e5b6 100644
--- a/arch/arm/mach-imx/mx6/clock.c
+++ b/arch/arm/mach-imx/mx6/clock.c
@@ -6,6 +6,7 @@
 #include <common.h>
 #include <command.h>
 #include <div64.h>
+#include <log.h>
 #include <asm/io.h>
 #include <linux/errno.h>
 #include <asm/arch/imx-regs.h>