param: Fix another off by 1 error and a formatting issue.

src/modules/systemlib/param/param.c

@@ -283,7 +283,7 @@ param_find_internal(const char *name, bool notification)
 			break;
 
 		} else if (ret < 0) {
-			last = middle - 1;
+			last = middle;
 
 		} else {
 			front = middle;

src/systemcmds/param/param.c

@@ -351,7 +351,7 @@ do_find(const char *name)
 		return 1;
 	}
 
-	printf("Found param %s at index %d\n", name, ret);
+	printf("Found param %s at index %lu\n", name, ret);
 	return 0;
 }