verify_package_compatibility() is added to parse the compatibility entry
(compatibility.zip) in a given OTA package. If entry is present, the
information is sent to libvintf to check the compatibility.

This CL doesn't actually call libvintf, since the API there is not
available yet.

Bug: 36597505
Test: Doesn't break the install with existing packages (i.e. w/o the
      compatibility entry).
Test: recovery_component_test
Change-Id: I3903ffa5f6ba33a5c0d761602ade6290c6752596