Add platform agnostic profiling support

[cameronrutherford]

roctx support was added during the hackathon by @PaulMullowney for AMD platforms, but we should abstract this to work for any backend supported similar to how ExaGO does.

This should be reflected as well in the spack package, and hopefully by the time we finish this, roctracer-dev's spack package works at the CMake level

[cameronrutherford]

This is the extension of #68

[cameronrutherford]

ROCm/rocprofiler#131 - according to this, roctracer-dev now works with Spack just fine. This isn't blocked as far as I can tell

[pelesh]

CC @superwhiskers