Enable Profile-Guided Optimization for V-Apps

[Profile-Guided Optimization](https://doc.rust-lang.org/rustc/profile-guided-optimization.html) should significantly improve code locality for complex V-Apps.

This will require changes in the VM in order to support the [necessary run-time components](https://rustc-dev-guide.rust-lang.org/profile-guided-optimization.html#runtime-aspects) for profiling.