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/drivers/fpga/xilinx.c b/drivers/fpga/xilinx.c
index 4b0334b..cbebefb 100644
--- a/drivers/fpga/xilinx.c
+++ b/drivers/fpga/xilinx.c
@@ -13,6 +13,7 @@
 
 #include <common.h>
 #include <fpga.h>
+#include <log.h>
 #include <virtex2.h>
 #include <spartan2.h>
 #include <spartan3.h>