tracepoints: Fix the descriptions of tracepoint_probe_register{_prio}

The description of tracepoint_probe_register duplicates
with tracepoint_probe_register_prio. This patch cleans up
the descriptions.

Link: http://lkml.kernel.org/r/20170616082643.7311-1-jlee@suse.com



Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>