markers: remove exported symbol marker_probe_cb_noarg()

marker_probe_cb_noarg() should not be seen by outer code.
this patch remove it.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Ingo Molnar <mingo@elte.hu>