tracing: remove unneeded variable

Impact: clean up.

Remove the unnecessary variable ret.

Signed-off-by: Wenji Huang <wenji.huang@oracle.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index f8ae2c5..c2e68d4 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -91,8 +91,6 @@
 
 int enable_branch_tracing(struct trace_array *tr)
 {
-	int ret = 0;
-
 	mutex_lock(&branch_tracing_mutex);
 	branch_tracer = tr;
 	/*
@@ -103,7 +101,7 @@
 	branch_tracing_enabled++;
 	mutex_unlock(&branch_tracing_mutex);
 
-	return ret;
+	return 0;
 }
 
 void disable_branch_tracing(void)