Staging: rtl8188eu: Remove extern as it is defined but never used

RTW_WPA_VERSION is removed as is declared and defined but
never used in the code.

Signed-off-by: Vatika Harlalka <vatikaharlalka@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --cc drivers/staging/rtl8188eu/core/rtw_ieee80211.c
Simple merge

diff --cc drivers/staging/rtl8188eu/include/ieee80211.h
Simple merge