[debuginfo-tests] Remove some unused config variables

debuginfo-tests/lit.site.cfg.py.in

 @LIT_SITE_CFG_IN_HEADER@
 
 import sys
 import lit.util
 
-config.test_exec_root = "@CMAKE_BINARY_DIR@"
-
 config.llvm_src_root = "@LLVM_SOURCE_DIR@"
-config.llvm_obj_root = "@LLVM_BINARY_DIR@"
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
 config.llvm_libs_dir = "@LLVM_LIBS_DIR@"
 config.llvm_shlib_dir = "@SHLIBDIR@"
 config.lit_tools_dir = "@LLVM_LIT_TOOLS_DIR@"
 config.llvm_plugin_ext = "@LLVM_PLUGIN_EXT@"
 config.debuginfo_tests_obj_root = "@DEBUGINFO_TESTS_BINARY_DIR@"
 config.debuginfo_tests_src_root = "@DEBUGINFO_TESTS_SOURCE_DIR@"
-config.has_lld = lit.util.pythonize_bool("@DEBUGINFO_TESTS_HAS_LLD@")
 config.host_triple = "@LLVM_HOST_TRIPLE@"
 config.target_triple = "@TARGET_TRIPLE@"
-config.host_arch = "@HOST_ARCH@"
 config.is_msvc = lit.util.pythonize_bool("@MSVC@")
 
 config.mlir_src_root = "@MLIR_SOURCE_DIR@"
 
 config.llvm_use_sanitizer = "@LLVM_USE_SANITIZER@"
 
 # Support substitution of the tools_dir with user parameters. This is
 # used when we can't determine the tool dir at configuration time.