net: use core MTU range checking in wireless drivers

- set max_mtu in wil6210 driver
- set max_mtu in atmel driver
- set min/max_mtu in cisco airo driver, remove airo_change_mtu
- set min/max_mtu in ipw2100/ipw2200 drivers, remove libipw_change_mtu
- set min/max_mtu in p80211netdev, remove wlan_change_mtu
- set min/max_mtu in net/mac80211/iface.c and remove ieee80211_change_mtu
- set min/max_mtu in wimax/i2400m and remove i2400m_change_mtu
- set min/max_mtu in intersil/hostap and remove prism2_change_mtu
- set min/max_mtu in intersil/orinoco
- set min/max_mtu in tty/n_gsm and remove gsm_change_mtu

CC: netdev@vger.kernel.org
CC: linux-wireless@vger.kernel.org
CC: Maya Erez <qca_merez@qca.qualcomm.com>
CC: Simon Kelley <simon@thekelleys.org.uk>
CC: Stanislav Yakovlev <stas.yakovlev@gmail.com>
CC: Johannes Berg <johannes@sipsolutions.net>
CC: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/wireless/intersil/hostap/hostap_main.c b/drivers/net/wireless/intersil/hostap/hostap_main.c
index 80d4228..1a16b8c 100644
--- a/drivers/net/wireless/intersil/hostap/hostap_main.c
+++ b/drivers/net/wireless/intersil/hostap/hostap_main.c
@@ -765,16 +765,6 @@ static void hostap_set_multicast_list(struct net_device *dev)
 }
 
 
-static int prism2_change_mtu(struct net_device *dev, int new_mtu)
-{
-	if (new_mtu < PRISM2_MIN_MTU || new_mtu > PRISM2_MAX_MTU)
-		return -EINVAL;
-
-	dev->mtu = new_mtu;
-	return 0;
-}
-
-
 static void prism2_tx_timeout(struct net_device *dev)
 {
 	struct hostap_interface *iface;
@@ -813,7 +803,6 @@ static const struct net_device_ops hostap_netdev_ops = {
 	.ndo_do_ioctl		= hostap_ioctl,
 	.ndo_set_mac_address	= prism2_set_mac_address,
 	.ndo_set_rx_mode	= hostap_set_multicast_list,
-	.ndo_change_mtu 	= prism2_change_mtu,
 	.ndo_tx_timeout 	= prism2_tx_timeout,
 	.ndo_validate_addr	= eth_validate_addr,
 };
@@ -826,7 +815,6 @@ static const struct net_device_ops hostap_mgmt_netdev_ops = {
 	.ndo_do_ioctl		= hostap_ioctl,
 	.ndo_set_mac_address	= prism2_set_mac_address,
 	.ndo_set_rx_mode	= hostap_set_multicast_list,
-	.ndo_change_mtu 	= prism2_change_mtu,
 	.ndo_tx_timeout 	= prism2_tx_timeout,
 	.ndo_validate_addr	= eth_validate_addr,
 };
@@ -839,7 +827,6 @@ static const struct net_device_ops hostap_master_ops = {
 	.ndo_do_ioctl		= hostap_ioctl,
 	.ndo_set_mac_address	= prism2_set_mac_address,
 	.ndo_set_rx_mode	= hostap_set_multicast_list,
-	.ndo_change_mtu 	= prism2_change_mtu,
 	.ndo_tx_timeout 	= prism2_tx_timeout,
 	.ndo_validate_addr	= eth_validate_addr,
 };
@@ -851,6 +838,8 @@ void hostap_setup_dev(struct net_device *dev, local_info_t *local,
 
 	iface = netdev_priv(dev);
 	ether_setup(dev);
+	dev->min_mtu = PRISM2_MIN_MTU;
+	dev->max_mtu = PRISM2_MAX_MTU;
 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 
 	/* kernel callbacks */