Fix problem with testcase timeouts not working. The timeout value was always multiplied with 10

since the $opt_valgrind variable was initialised to 0, thus being "defined"

mysql-test/mysql-test-run.pl

@@ -848,13 +848,13 @@ sub command_line_setup () {
   if ( ! $opt_testcase_timeout )
   {
     $opt_testcase_timeout= $default_testcase_timeout;
-    $opt_testcase_timeout*= 10 if defined $opt_valgrind;
+    $opt_testcase_timeout*= 10 if $opt_valgrind;
   }
 
   if ( ! $opt_suite_timeout )
   {
     $opt_suite_timeout= $default_suite_timeout;
-    $opt_suite_timeout*= 6 if defined $opt_valgrind;
+    $opt_suite_timeout*= 6 if $opt_valgrind;
   }
 
   # Increase times to wait for executables to start if using valgrind