torture: Replace torture_init_begin string with %s

This commit replaces a hard-coded "torture_init_begin" string in
a pr_alert() format with "%s" and __func__.
Signed-off-by: Stephen Zhang <stephenzhangzsd@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

kernel/torture.c

@@ -816,9 +816,9 @@ bool torture_init_begin(char *ttype, int v)
 {
 	mutex_lock(&fullstop_mutex);
 	if (torture_type != NULL) {
-		pr_alert("torture_init_begin: Refusing %s init: %s running.\n",
-			 ttype, torture_type);
-		pr_alert("torture_init_begin: One torture test at a time!\n");
+		pr_alert("%s: Refusing %s init: %s running.\n",
+			  __func__, ttype, torture_type);
+		pr_alert("%s: One torture test at a time!\n", __func__);
 		mutex_unlock(&fullstop_mutex);
 		return false;
 	}