doc: fix typo in feature-removal-schedule

Index: wireless-2.6/Documentation/feature-removal-schedule.txt
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@@ -343,7 +343,7 @@ Who:	John W. Linville <linville@tuxdrive
 
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-What:	iee80211 softmac wireless networking component
+What:	ieee80211 softmac wireless networking component
 When:	2.6.26 (or after removal of bcm43xx and port of zd1211rw to mac80211)
 Files:	net/ieee80211/softmac
 Why:	No in-kernel drivers will depend on it any longer.