staging: rtl8723bs: remove rtw_change_ifname

Delete function rtw_change_ifname because it is not used.

Signed-off-by: Nam Cao <namcaov@gmail.com>
Link: https://lore.kernel.org/r/975cd771e5b6573b84b31690895d140cbdaeb5e2.1662111798.git.namcaov@gmail.com


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