staging: rtl8723bs: remove unused function write_cam_from_cache

Function write_cam_from_cache in rtw_wlan_util.c is never used,
so remove it.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20190926175933.44967-1-straube.linux@gmail.com


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