Remove unnecessary and incorrect add_suppression.

Changes to be committed:
	modified:   mysql-test/suite/sys_vars/r/wsrep_cluster_address_basic.result
	modified:   mysql-test/suite/sys_vars/t/wsrep_cluster_address_basic.test

mysql-test/suite/sys_vars/r/wsrep_cluster_address_basic.result

 #
 # wsrep_cluster_address
 #
-call mtr.add_suppression("safe_mutex: Found wrong usage of mutex.*");
 # save the initial value
 SET @wsrep_cluster_address_global_saved = @@global.wsrep_cluster_address;
 # default

mysql-test/suite/sys_vars/t/wsrep_cluster_address_basic.test

@@ -4,8 +4,6 @@
 --echo # wsrep_cluster_address
 --echo #
 
-call mtr.add_suppression("safe_mutex: Found wrong usage of mutex.*");
-
 --echo # save the initial value
 SET @wsrep_cluster_address_global_saved = @@global.wsrep_cluster_address;