tracing: remove recording function depth from trace_printk

The function depth in trace_printk was to facilitate the function
graph output. Now that the function graph calculates the depth within
the trace output, we no longer need to record the depth when the
trace_printk is called.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>

kernel/trace/trace_mmiotrace.c

@@ -359,5 +359,5 @@ void mmio_trace_mapping(struct mmiotrace_map *map)
 
 int mmio_trace_printk(const char *fmt, va_list args)
 {
-	return trace_vprintk(0, -1, fmt, args);
+	return trace_vprintk(0, fmt, args);
 }