Move libtinyxml to vendor partition

No system component is using this, but some vendor-specific libs are.
Moving this to vendor partition so that we don't need to shipt this
library in the generic system image.

Bug: 36856960
Test: libtinyxml.so in vendor parititon
Change-Id: I1d7785bbedbaee6af1a39ed8d6ebc441549d7b2d