staging: rtl8192e: Remove dead code from struct rtl819x_ops

Remove entry .rx_command_packet_handler, .irq_clear and
.init_before_adapter_start as it is dead code.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/93427f1b2ad5841451d7e8cc8a621d7eff8cd916.1677010997.git.philipp.g.hortmann@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>