cfg80211-wext: export symbols only when needed

When a fully converted cfg80211 driver needs cfg80211-wext for
userspace API purposes, the symbols need not be exported. When
other drivers (orinoco/hermes or ipw2200) are enabled, they do
need the symbols exported as they use them directly.

Make those drivers select a new CFG80211_WEXT_EXPORT Kconfig
symbol (instead of just CFG80211_WEXT) and export the functions
only if requested - this saves about 1/2k due to the size of
EXPORT_SYMBOL() itself.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/Kconfig b/net/wireless/Kconfig
index 29c8675..b13dfb4 100644
--- a/net/wireless/Kconfig
+++ b/net/wireless/Kconfig
@@ -178,10 +178,18 @@
 	bool "cfg80211 wireless extensions compatibility"
 	depends on CFG80211
 	select WEXT_CORE
+	default y if CFG80211_WEXT_EXPORT
 	help
 	  Enable this option if you need old userspace for wireless
 	  extensions with cfg80211-based drivers.
 
+config CFG80211_WEXT_EXPORT
+	bool
+	depends on CFG80211
+	help
+	  Drivers should select this option if they require cfg80211's
+	  wext compatibility symbols to be exported.
+
 config LIB80211
 	tristate
 	default n