ioping(1): fix aio description

Signed-off-by: Kir Kolyshkin <kir@openvz.org>

ioping.1

@@ -63,7 +63,7 @@ Print raw statistics for every \fIperiod\fR requests (see format below).
 Print raw statistics for every \fIperiod\fR in time.
 .TP
 .B \-A
-Use asynchronous I/O (syscalls \fBio_submit\fR(2), \fBio_submit\fR(2), etc).
+Use asynchronous I/O (\fBio_setup\fR(2), \fBio_submit\fR(2) etc syscalls).
 .TP
 .B \-B
 Batch mode. Be quiet and print final statistics in raw format.