Allow public profile compilation for primary apks

It is ok to perform a "public" compilation with
profiles comming from dex metdata files.

The PackageManager is responsible to set the is_public flag for
primary apks; so we no longer check it in installd.

Test: installd_dexopt_test
Bug: 30934496
Change-Id: I72519c6a05aa318985396c6f93176624fe76c4be