This changes the help text of a couple of commands in tracepoint.c to
follow the GNU style.
ChangeLog
2018-04-29 Tom Tromey <tom@tromey.com>
* tracepoint.c (_initialize_tracepoint): Update help text.
testsuite/ChangeLog
2018-04-30 Tom Tromey <tom@tromey.com>
* gdb.trace/tfind.exp: Update help tests.