network_3GSmokeTest: Run with wardmodem.

Update network_3GSmokeTest to use a wardmodem context. By default this context
is a noop.
Also add a control file to run the test with wardmodem.

BUG=chromium:263191
TEST=run network_3GSmokeTest.wardmodem

Change-Id: I295c2076a47ea9a7c5a7f3fda719e74c23ba2c3d
Reviewed-on: https://chromium-review.googlesource.com/169222
Reviewed-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Prathmesh Prabhu <pprabhu@chromium.org>
Tested-by: Prathmesh Prabhu <pprabhu@chromium.org>
2 files changed