nmeter: fix bug where %[mf] behaves as %[mt]

diff --git a/procps/nmeter.c b/procps/nmeter.c
index 5730529..7ab2865 100644
--- a/procps/nmeter.c
+++ b/procps/nmeter.c
@@ -625,7 +625,7 @@
 		put_question_marks(4);
 		return;
 	}
-	if (s->opt == 'f') {
+	if (s->opt == 't') {
 		scale(m_total << 10);
 		return;
 	}