staging: rtl8723bs: remove unused variable from rtw_os_recv_indicate_pkt

staging: rtl8723bs: remove unused variable from rtw_os_recv_indicate_pkt

Remove unused 'ret' variable from rtw_os_recv_indicate_pkt function in
drivers/staging/rtl8723bs/os_dep/recv_linux.c as nothing is actually
done with it. A function return val is conditionally stored to it under
certain circumstances, but nothing is done with it after. Fixes a
warning from kernel test robot.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210406105607.1689292-1-phil@philpotter.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>