runtest/mm: Fix mmapstress01 entry

-t option was removed in 88321bf. This fixes test failure:

mmapstress01: invalid option -- 't'
...
tst_test.c:673: TBROK: Invalid option

Fixes: 88321bf ("mmapstress01: refactor to tst_test framework")

Signed-off-by: Petr Vorel <pvorel@suse.cz>

runtest/mm

@@ -41,7 +41,7 @@ shmt10 shmt10
 shm_test01	shm_test -l 10 -t 2
 mallocstress01	mallocstress
 
-mmapstress01 mmapstress01 -p 20 -t 0.2
+mmapstress01 mmapstress01 -p 20
 mmapstress02 mmapstress02
 mmapstress03 mmapstress03
 mmapstress04 mmapstress04