Pass LLVM_LIBDIR_SUFFIX over to dotest, and append it to 'lib' whenthe correct library directory from CMake to dotest.py when linking
linking liblldb. This fixes link failures when tests are run withinliblldb, instead of trying to reconstruct the path from executable path.
stand-alone buildThis fixes link failures on systems where platforms having non-null
LLVM_LIBDIR_SUFFIX is not empty.