gm45: Don't crash if less than 4G of RAM are present.

In such setup there is no resource 5. find_resource die()s if no resource is
present. Use probe_resource instead.

Change-Id: I6eb4a9d8712295c58281ee69ab129276d784ca2e
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/7438
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Tested-by: build bot (Jenkins)

src/northbridge/intel/gm45/northbridge.c

@@ -177,7 +177,7 @@ static void mch_domain_set_resources(device_t dev)
 
 	for (i = 3; i < 8; ++i) {
 		/* Report read resources. */
-		resource = find_resource(dev, i);
+		resource = probe_resource(dev, i);
 		if (resource)
 			report_resource_stored(dev, resource, "");
 	}