can: ti_hecc: Fix napi poll return value for repoll

BugLink: http://bugs.launchpad.net/bugs/1745047

commit f6c23b17 upstream.

After commit d75b1ade ("net: less interrupt masking in NAPI") napi
repoll is done only when work_done == budget.
So we need to return budget if there are still packets to receive.
Signed-off-by: Oliver Stäbler <oliver.staebler@bytesatwork.ch>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

drivers/net/can/ti_hecc.c

@@ -652,6 +652,9 @@ static int ti_hecc_rx_poll(struct napi_struct *napi, int quota)
 		mbx_mask = hecc_read(priv, HECC_CANMIM);
 		mbx_mask |= HECC_TX_MBOX_MASK;
 		hecc_write(priv, HECC_CANMIM, mbx_mask);
+	} else {
+		/* repoll is done only if whole budget is used */
+		num_pkts = quota;
 	}
 
 	return num_pkts;