net/usb: initiate sync sequence in sierra_net.c driver

The following patch adds the initiation of the sync sequence to
"sierra_net_bind()". If this step is omitted, the modem will never sync up
with the host and it will not be possible to establish a data connection.

Signed-off-by: Elina Pasheva <epasheva@sierrawireless.com>
Signed-off-by: Rory Filer <rfiler@sierrawireless.com>
Tested-by: Elina Pasheva <epasheva@sierrawireless.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/usb/sierra_net.c b/drivers/net/usb/sierra_net.c
index a44f9e0..f1942d6 100644
--- a/drivers/net/usb/sierra_net.c
+++ b/drivers/net/usb/sierra_net.c
@@ -789,6 +789,9 @@
 	/* prepare sync message from template */
 	memcpy(priv->sync_msg, sync_tmplate, sizeof(priv->sync_msg));
 
+	/* initiate the sync sequence */
+	sierra_net_dosync(dev);
+
 	return 0;
 }