[Libomptarget] Run CPU offloading tests using the new driver

This patch adds a new target to the OpenMP CPU offloading tests. This
tests the usage of the new driver for CPU offloading. If this all works
then we can move to transition to the new driver as the default.

Depends on D119613

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D119736