ktest: Start failure timeout on panic too

Currently we just look for a Call Trace to start the time out
when to reboot the box. But if the kernel panics and does not
show a Call Trace, the test will not reboot the box after
the specified timeout.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

tools/testing/ktest/ktest.pl

@@ -820,6 +820,7 @@ sub monitor {
 	}
 
 	if ($full_line =~ /Kernel panic -/) {
+	    $failure_start = time;
 	    $bug = 1;
 	}