infrun.c:handle_inferior_event: Make process_event_stop_test label a function.

infrun.c:handle_inferior_event: Make process_event_stop_test label a function.

Now that all ecs->random_signal handing is always done before the
'process_event_stop_test' label, we can easily make that a real
function and actually give it a describing comment that somewhat makes
sense.

Reindenting the new function will be handled in a follow up patch.

2013-10-28  Pedro Alves  <palves@redhat.com>

	* infrun.c (process_event_stop_test): New function, factored out
	from handle_inferior_event.
	(handle_inferior_event): 'process_event_stop_test' is now a
	function instead of a goto label -- adjust.