Fix default HIP_VDI_HOME
Fix default HIP_VDI_HOME

There is soft link /opt/rocm/bin/.hipVersion, therefore when hipcc is executed
as /opt/rocm/bin/hipcc, it will set HIP_VDI_HOME to /opt/rocm, which is
incorrect. Check ../lib/bitcode instead to identify HIP_VDI_HOME.

GPUOpen-ProfessionalCompute-Tools/HIP,GPUOpen-ProfessionalCompute-Tools/HIP,GPUOpen-ProfessionalCompute-Tools/HIP,GPUOpen-ProfessionalCompute-Tools/HIP,GPUOpen-ProfessionalCompute-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP