fsl/fman: fix the pause_time test

pause_time is unsigned so it can't be less than zero.  The bug means
that we allow invalid pause-times.

Fixes: 57ba4c9b56d8 ('fsl/fman: Add FMan MAC support')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/fman/fman_dtsec.c

@@ -934,7 +934,7 @@ int dtsec_set_tx_pause_frames(struct fman_mac *dtsec,
 
 	/* FM_BAD_TX_TS_IN_B_2_B_ERRATA_DTSEC_A003 Errata workaround */
 	if (dtsec->fm_rev_info.major == 2)
-		if (pause_time < 0 && pause_time <= 320) {
+		if (pause_time <= 320) {
 			pr_warn("pause-time: %d illegal.Should be > 320\n",
 				pause_time);
 			return -EINVAL;