common: Drop image.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/board/aristainetos/aristainetos.c b/board/aristainetos/aristainetos.c
index 7067103..5095cf6 100644
--- a/board/aristainetos/aristainetos.c
+++ b/board/aristainetos/aristainetos.c
@@ -9,6 +9,7 @@
  * Author: Fabio Estevam <fabio.estevam@freescale.com>
  */
 
+#include <image.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/imx-regs.h>
 #include <asm/arch/iomux.h>