Pass the supportQ flag to stats-log-api-gen

Statsd is becoming a Mainline module in R. As part of that effort,
the logging schema has been updated. However, mainline modules
using statsd that are updated in Q still need to use the legacy
schema.
So we've added support for that in the autogeneration tool by
passing a
flag to support legacy logging schema.

Note: this change is not needed if this module will not be
updated in Q.

Bug: 145624233
Test: m
Test: flashes successfully
Change-Id: I1417512bcaec6074c984da1dd19144277094820e