Support labeling files on the root partition other than os_t. e.g., local_t, cache_t.

[pengubco]

What I'd like:
Have some defined path(s) on the root partition to use a label other than os_t. For example, label /usr/cache-t/* as cache-t, label /usr/local-t/* as local-t.

Why I want this feature?
I need to store some read-only files on the root partition. But those files are data files, say a db file. Or binaries that not supposed to executed by host or kernel. So os_t doesn't fit.

Any alternatives you've considered: