greybus: interface: Pass interface pointer to gb_interface_remove()

The callers already have a valid interface pointer and there is no need
for gb_interface_remove() to find the interface again.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>