Add recovery support of dynamic fingerprints

After http://go/aog/1306461, the metadata in the OTA package can have
multiple fingerprints or device names
e.g. from pre-device=lmiin to pre-device=lmiin|lmiinpro

This CL updates recovery code to recognize them

Test: Added unit tests for this
Bug: 159850736
Change-Id: If6315bf2d3dea77abb9d7d83145f55b0148cdfb1