mwifiex: add "ethtool wol" command support

Host sleep wakeup condition is configured using this command.

Supports Wake-on: pumb

For examples:

wake-on any unicast packets:
ethtool -s mlan0 wol u

wake-on multicast/broadcast packet:
ethtool -s mlan0 wol mb

wake-on unicast packets and MAC events:
ethtool -s mlan0 wol pu

wake-on unicast/multicast/broadcast packets and MAC events:
ethtool -s mlan0 wol pmbu

disable all wake-on options:
ethtool -s mlan0 wol d

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/mwifiex/main.h b/drivers/net/wireless/mwifiex/main.h
index 553adfb..989e05e 100644
--- a/drivers/net/wireless/mwifiex/main.h
+++ b/drivers/net/wireless/mwifiex/main.h
@@ -1103,6 +1103,8 @@
 int mwifiex_del_mgmt_ies(struct mwifiex_private *priv);
 u8 *mwifiex_11d_code_2_region(u8 code);
 
+extern const struct ethtool_ops mwifiex_ethtool_ops;
+
 #ifdef CONFIG_DEBUG_FS
 void mwifiex_debugfs_init(void);
 void mwifiex_debugfs_remove(void);