drivers/intel/fsp1_1: Include rules.h in util.h

util.h uses ENV_* and hence needs to have rules.h

This is required for successful compilation of strago.

Change-Id: I0df35e90e2010aac43ef0a4d900f20c842d3bcb5
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: http://review.coreboot.org/12495
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

src/drivers/intel/fsp1_1/include/fsp/util.h

@@ -17,6 +17,7 @@
 #ifndef FSP1_1_UTIL_H
 #define FSP1_1_UTIL_H
 
+#include <rules.h>
 #include <fsp/api.h>
 /* Current users expect to get the SoC's FSP definitions by including util.h. */
 #include <fsp/soc_binding.h>