Enable virtual memory examples for CUDA

[j-stephan]

Motivation

Due to a bug in ROCm < 7.1, virtual memory didn't work correctly for CUDA GPUs. Since ROCm 7.1 was released a while ago, we can now enable these examples.

Technical Details

Removes the guards against CUDA from the virtual memory CMake files.

Test Plan

Tested locally.

Test Result

Works.

Added/Updated documentation?

• Yes
• No, does not apply to this PR.

Included Visual Studio files?

• Yes
• No, does not apply to this PR.

Submission Checklist

• New examples contain proper CMake and Make files.
• I have updated relevant CI workflows and the new examples are being built and tested in CI.
• Check and guard against unsupported ASICs if relevant dependent libraries have limited support.
• Look over the contributing guidelines at https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

[j-stephan]

We need to wait for 7.2 due to other CUDA-related bugs.