Fix VintfObject to use vintf

VintfObject is a TestApi class and used by CTS tests and EDI collectors.
Previously, it used libvintf to open VINTF data from device which caused
SEPolicy error because
- CTS tests and EDI collectors are "apps"
- VINTF data needs to load files unavailable to apps.

In this change, VintfObject uses "instrumentation" to get VINTF data by
calling /system/bin/vintf under shell identity.

Bug: 338278029
Bug: 317747397
Test: atest SELinuxNeverallowRulesTest
Test: VintfDeviceInfo/VintfFilesCollector work
Change-Id: I43a54827a1d82cfaf573753c5c5862425843a099