Remove hip-hcc codes from hip code base
Simplify hip CMakeLists.txt to exclude hip-hcc
Simplify cmake cmd for hip-rocclr building
Some minor fixes
Change-Id: I1ae357ecfd638d6c25bca293c1724b026be21ecd
[ROCm/clr commit: 1cba7ec965]
* reimplement HIP_INIT as a function, expose it as hip_impl::hip_init()
so that it could be called from hipLaunchKernelGGL and other inlined
HIP functions
* Don't call hip_init from ihipPreLaunchKernel
[ROCm/clr commit: fa9495841b]