Fix a test that always failed on --embedded

mysql-test/suite/innodb/r/innodb-lru-force-no-free-page.result

-call mtr.add_suppression("\\[Warning\\] InnoDB: Difficult to find free blocks in the buffer pool.");
+call mtr.add_suppression("InnoDB: Difficult to find free blocks in the buffer pool");
+SET @saved_debug = @@SESSION.debug_dbug;
 SET SESSION debug_dbug="+d,ib_lru_force_no_free_page";
 CREATE TABLE t1 (j LONGBLOB) ENGINE = InnoDB;
 BEGIN;
 INSERT INTO t1 VALUES (repeat('abcdefghijklmnopqrstuvwxyz',200));
 COMMIT;
-SET SESSION debug_dbug="";
+SET debug_dbug = @saved_debug;
 DROP TABLE t1;
 FOUND /InnoDB: Difficult to find free blocks / in mysqld.1.err

mysql-test/suite/innodb/t/innodb-lru-force-no-free-page.test

 --source include/have_innodb.inc
 --source include/have_debug.inc
+--source include/not_embedded.inc
 
-call mtr.add_suppression("\\[Warning\\] InnoDB: Difficult to find free blocks in the buffer pool.");
+call mtr.add_suppression("InnoDB: Difficult to find free blocks in the buffer pool");
 
+SET @saved_debug = @@SESSION.debug_dbug;
 SET SESSION debug_dbug="+d,ib_lru_force_no_free_page";
 
 CREATE TABLE t1 (j LONGBLOB) ENGINE = InnoDB;
@@ -10,7 +12,7 @@ BEGIN;
 INSERT INTO t1 VALUES (repeat('abcdefghijklmnopqrstuvwxyz',200));
 COMMIT;
 
-SET SESSION debug_dbug="";
+SET debug_dbug = @saved_debug;
 
 DROP TABLE t1;
 
@@ -21,4 +23,3 @@ let SEARCH_RANGE= -50000;
 let SEARCH_FILE= $MYSQLTEST_VARDIR/log/mysqld.1.err;
 --let SEARCH_PATTERN=InnoDB: Difficult to find free blocks 
 --source include/search_pattern_in_file.inc
-