staging: r8188eu: remove unused enum hal_intf_ps_func

HAL_USB_SELECT_SUSPEND and HAL_MAX_ID are both unused,
so enum hal_intf_ps_func can be removed.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20210906190223.11396-13-straube.linux@gmail.com


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