staging: rtl8187se: Remove initialization of static variable in ieee80211/ieee80211_softmac.c

Fix checkpatch.pl errors:
ERROR: do not initialise statics to 0 or NULL

Signed-off-by: Ana Rey <anarey@gmail.com>
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>