tracing: Remove redundant check on field->field in histograms

The check on field->field being true is handled as the first check
on the cascaded if statement, so the later checks on field->field
are redundant because this clause has already been handled. Since
this later check is redundant, just remove it.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241107120530.18728-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Author: ColinIanKing

kernel/trace/trace_events_hist.c

@@ -1354,10 +1354,7 @@ static const char *hist_field_name(struct hist_field *field,
 	} else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
 		field_name = "common_timestamp";
 	else if (field->flags & HIST_FIELD_FL_STACKTRACE) {
-		if (field->field)
-			field_name = field->field->name;
-		else
-			field_name = "common_stacktrace";
+		field_name = "common_stacktrace";
 	} else if (field->flags & HIST_FIELD_FL_HITCOUNT)
 		field_name = "hitcount";