staging: rtl8192u: remove ieee80211_crypt.h

This patch removes ieee80211_crypt.h because this header file is the same as
ieee80211/ieee80211_crypt.h and the structures and functions declared in it
are used directly only inside ieee80211/.

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>