selftests: tracing: Use mutex_unlock for testing glob filter

Since commit c5b6ababd21a ("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/[e-mail]
Signed-off-by: Masami Hiramatsu (Google) <[e-mail]>
Acked-by: Steven Rostedt (Google) <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

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

···
 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.