cellular: Add network3g_pseudomodem test suite.

Created a new test suite to run pseudomodem tests that gets kicked off
after every build.

BUG=chromium:238576
CQ-DEPEND=I752425b1d7c685d0e5ba1dc67245a8740ebaa6e6
TEST=Run suite:network3g_pseudomodem. It should pass.

Change-Id: I9f1ca38fa9f5dac5ce3ee1e24a9089296315840d
Reviewed-on: https://gerrit.chromium.org/gerrit/50714
Commit-Queue: Arman Uguray <armansito@chromium.org>
Tested-by: Arman Uguray <armansito@chromium.org>
Reviewed-by: Prashanth Balasubramanian <beeps@chromium.org>
3 files changed