rtl8187: remove priv->mode

It is checked in add_interface, but there it is easily replaced with
a check of priv->vif.  If that information should become necessary,
it is available in vif->type anyway.

It is also checked in led_turn_on and led_turn_off, where I made the
substitutions as described above.  Of course, these checks seem to
have been incorrect since the driver was using NL80211_IFTYPE_MONITOR
to indicate no interface rather than NL80211_IFTYPE_UNSPECIFIED.
Anyway, I think these checks may be extraneous...?

Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rtl818x/rtl8187.h b/drivers/net/wireless/rtl818x/rtl8187.h
index 6af0f3f..6bb3211 100644
--- a/drivers/net/wireless/rtl818x/rtl8187.h
+++ b/drivers/net/wireless/rtl818x/rtl8187.h
@@ -92,7 +92,7 @@
 	struct rtl818x_csr *map;
 	const struct rtl818x_rf_ops *rf;
 	struct ieee80211_vif *vif;
-	int mode;
+
 	/* The mutex protects the TX loopback state.
 	 * Any attempt to set channels concurrently locks the device.
 	 */