VtsTrebleVintfTest: Port ODM Manifest reads.

system/libvintf can't be modified in vts release, so
the code to read an odm manifest has temporarily been copied
here for the O branch only. On ToT, this code will not
be present.

Bug: 77293161
Test: vts_treble_vintf_test passes
      on Android O release marlin userdebug
Test: verify /odm/etc/manifest.xml is read by putting a manifest
      there and running the test can make the test fail.

Change-Id: I8347e9cf9521a5e65437d0fc16b4c0a5e677612c
Merged-In: I8347e9cf9521a5e65437d0fc16b4c0a5e677612c
5 files changed