tracing: initialize variable in create_dyn_event()

Fix compile warning in create_dyn_event(): 'ret' may be used uninitialized
in this function [-Wuninitialized].

Link: http://lkml.kernel.org/r/1553237900-8555-1-git-send-email-frowand.list@gmail.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 5448d44c ("tracing: Add unified dynamic event framework")
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/trace_dynevent.c

@@ -74,7 +74,7 @@ int dyn_event_release(int argc, char **argv, struct dyn_event_operations *type)
 static int create_dyn_event(int argc, char **argv)
 {
 	struct dyn_event_operations *ops;
-	int ret;
+	int ret = -ENODEV;
 
 	if (argv[0][0] == '-' || argv[0][0] == '!')
 		return dyn_event_release(argc, argv, NULL);