dlopen() fixes (#929)

* Initial attempt to switch over to internally linked state.

* Add missing CMake update.

* hipLaunchKernelGGLImpl must be inline as well. Ensure internal linkage.

* Ensure global retrieval uses internally linked state.

* Hide HC in the implementation. Minimise ADL woes.

* Strange software exists, and must be catered to.

* Use a less spammy mechanism for ensuring internal linkage / non-export.

* Remove leftover internal detail.

CMakeLists.txt

@@ -240,7 +240,6 @@ if(HIP_PLATFORM STREQUAL "hcc")
         src/hip_surface.cpp
         src/hip_intercept.cpp
         src/env.cpp
-        src/program_state.cpp
         src/h2f.cpp)
 
     execute_process(COMMAND ${HCC_HOME}/bin/hcc-config --ldflags OUTPUT_VARIABLE HCC_LD_FLAGS)