selftests: tracing: Use mutex_unlock for testing glob filter

Since commit c5b6aba ("locking/mutex: implement
mutex_trylock_nested") makes mutex_trylock() as an inlined
function if CONFIG_DEBUG_LOCK_ALLOC=y, we can not use
mutex_trylock() for testing the glob filter of ftrace.

Use mutex_unlock instead.

Link: https://lore.kernel.org/r/175151680309.2149615.9795104805153538717.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Author: mhiramat

tools/testing/selftests/ftrace/test.d/ftrace/func-filter-glob.tc

@@ -29,7 +29,7 @@ ftrace_filter_check 'schedule*' '^schedule.*$'
 ftrace_filter_check '*pin*lock' '.*pin.*lock$'
 
 # filter by start*mid*
-ftrace_filter_check 'mutex*try*' '^mutex.*try.*'
+ftrace_filter_check 'mutex*unl*' '^mutex.*unl.*'
 
 # Advanced full-glob matching feature is recently supported.
 # Skip the tests if we are sure the kernel does not support it.