staging: rtl8723bs: core: rtw_mlme_ext.c: Remove set but unused variable

Removed set but unused 'reason_code' variable. Issue detected by GCC
running with the warning option -Wunused-but-set-variable.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Link: https://lore.kernel.org/r/20210524113433.25923-1-fmdefrancesco@gmail.com


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