[Init] Create dir for odsign metrics

This is required so that system_server can read/delete the file(s) in
/data/misc/odsign/metrics & report to statsd

Note the group change in odsign directory was required so that
system_server can get the execute permission to read file in the sub dir

Test: adb shell ls -l /data/misc/odsign/metrics
Bug: 202926606
Change-Id: I6dd80e05bbfb9daf4aa3e996fc22bba1de8bd2ce