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/common/spl/spl.c b/common/spl/spl.c
index 6b1d41e..7ea0b06 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -15,6 +15,7 @@
 #include <hang.h>
 #include <init.h>
 #include <irq_func.h>
+#include <log.h>
 #include <serial.h>
 #include <spl.h>
 #include <asm/u-boot.h>