UPSTREAM: net: qmi_wwan: use a single bind function for all device types

UPSTREAM: net: qmi_wwan: use a single bind function for all device types

Refactoring the bind code lets us use a common driver_info struct
for all supported devices, simplifying the code a bit.  The
real advantage is that devices using the CDC ECM interface
layout now also can be added dynamically using the new_id sysfs
interface.  This simplifies testing of new devices.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit bd877e489126b2214f971ae8ef7bd17b48a94a7b)

Change-Id: I94d77f53b09d51094d57e215fe08741cef12fc49
Signed-off-by: Ben Chan <benchan@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/35028
Reviewed-by: Olof Johansson <olofj@chromium.org>