[fvm-host] Convert compress enum to flags

This CL replaces the compress_type_t to a uint32_t flags field.
This allows other values to be plumbed through, like one for
fvm::kSparseFlagZxcrypt.

Change-Id: I030a749947f5a02402ddf2b9fbe528ee98900911

[fvm] Add host & target side support for compressed sparse file

Change-Id: I2ba9350cfbc98e96de7fc0a7a253e9c560ba208b

[minfs][blobstore][fvm] Relocate host-side tools to /host

Change-Id: I21e3f17a7dd926dc5038af85edc0e2e016d220bd