GitLab

* Remove setting of link libraries, include and link dirs and compile
  flags for each target, instead let Cmake deal with them by linking the
  main library to hip::host hiprtc::hiprtc hip::hipfft;
* Fix: custom command without ADD_CUSTOM_TARGET and ADD_DEPENDENCIES is
  executed for both static and shared targets;
* Remove IF(APPLE) parts.

* Converted RPMD plugin to common platform

* Merged RPMD tests for different platforms

* Try to fix errors on CPU OpenCL

Plugins work with CPU platform.  This involved separating the reference implementations of plugins into their own libraries.