Unconditionally install com.android.virt APEX

The change in the packages/modules/Virtualization in the same topic
takes care for defining the right variant of the APEX to be installed:

* Devices with AVF support will get the full com.android.virt APEX
* Devices without AVF support will get an almost empty version that only
  contains an app that defines AVF-related permissions, and soon the BCP
  fragment jar.

Bug: 243512044
Test: build & flash oriole
Test: build & flash redfin
Change-Id: I2c38e03529a77dd2820212812433741725115ce0