Move trusty coverage files to /data/vendor/trusty

Currently on the coverage builds of trusty, the coverage information is
being dumped at /data/local/tmp. But it has neverallow rules that forbid services from reading writing to it. Moving it to the recommended /vendor/data/ folder

Bug: 440261900
Change-Id: Ifa4c6248ee66836816346a43a95a714621e58fc2