staging: rtl8723bs: remove unused offset in phase 2 _BlockWrite()

staging: rtl8723bs: remove unused offset in phase 2 _BlockWrite()

Commit c1314fe4d28f ("staging: rtl8723bs: remove all RT_TRACE logs
in hal/ and os_dep/") removed the unnecessary RT_TRACE logs in hal/
and os_dep/ files, but left the variable "offset" in the Phase 2
_BlockWrite() function unused, so delete it.

This is reported by Coverity Scan with CID 1408950 as UNUSED_VALUE.

Signed-off-by: Robertus Diawan Chris <robertusdchris@gmail.com>
Reviewed-by: Luka Gejak <luka.gejak@linux.dev>
Reviewed-by: Ethan Tidmore <ethantidmore06@gmail.com>
Link: https://patch.msgid.link/20260420044651.164450-1-robertusdchris@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>