Support LLPC_PATH in amdllpc
Support LLPC_PATH in amdllpc

Replace $(ICD_DEPTH)/api/llpc with $(LLPC_DEPTH) in Makefile.apillpctool. It is missed in original change.

googlestadia/llpc,GPUOpen-Drivers/llpc,googlestadia/llpc,googlestadia/llpc,GPUOpen-Drivers/llpc,GPUOpen-Drivers/llpc,GPUOpen-Drivers/llpc,googlestadia/llpc,GPUOpen-Drivers/llpc,googlestadia/llpc