staging: rtl8723bs: hal: rtl8723b_cmd.c: Remove variables

Remove variables that are declared and initialised but never used.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>