staging: rtl8192u: make in ieee80211/ieee80211_rx.c some local functions static

Make some local functions (AddReorderEntry, RxReorderIndicate and
parse_subframe) static and fix coding style in this function
declarations when It is necessary.

Fix the following sparse warnings in ieee80211/ieee80211_rx.c

drivers/staging/rtl8192u/ieee80211/ieee80211_rx.c:521:1: warning: symbol 'AddReorderEntry' was not declared. Should it be static?
drivers/staging/rtl8192u/ieee80211/ieee80211_rx.c:604:6: warning: symbol 'RxReorderIndicatePacket' was not declared. Should it be static?
drivers/staging/rtl8192u/ieee80211/ieee80211_rx.c:774:4: warning: symbol 'parse_subframe' was not declared. Should it be static?

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