staging: rtl8723bs: replace WIFI_REASON_CODE

Replace unique macros and WIFI_REASON_CODE enum with the kernel provided
ieee80211_reasoncode.

Signed-off-by: Ross Schmidt <ross.schm.dev@gmail.com>
Link: https://lore.kernel.org/r/20201206034517.4276-2-ross.schm.dev@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>