Add support for hipconfig to display details on HIP-Clang compiler and update HIP_COMPILER and HIP_RUNTIME to include clang and rocclr. Also, add hipcc flags --cxxflags and --ldflags to support HCC users who used hccconfig flags.
Change-Id: Ib12d81a4ff59d34fb000626836b1adb10be3ac61
[ROCm/hip commit: afc9b546fb]