New 'modem status' implementation for cromo and ModemManager1.

This CL provides a new implementation of 'modem status' that handles
both cromo and ModemManager1, and supercedes the mm-status script. It
also adds 'modem status-feedback', which is similar to 'modem status'
but tailors output for feedback reports.

TEST=Test `modem status` and `modem status -d` with modems supported by
cromo and ModemManager1.

Change-Id: I9f51b493c80e07611855b528ca6de230dfeac3d4
Tested-by: Ben Chan <>
Reviewed-by: Thieu Le <>
Commit-Ready: Ben Chan <>
4 files changed