message: Remove LIEF_ROOT
diff: set(_LIEF_SEARCHES)
  -# Search LIEF_ROOT first if it is set.
  +
  if(LIEF_ROOT)
  - message(DEPRECATION "LIEF_ROOT is deprecated. Please use LIEF_DIR")
  - set(_LIEF_SEARCH_ROOT PATHS ${LIEF_ROOT} NO_DEFAULT_PATH)
  - list(APPEND _LIEF_SEARCHES _LIEF_SEARCH_ROOT)
  + message(FATAL_ERROR "LIEF_ROOT is no longer supported. Please use LIEF_DIR")
  endif()
  if(LIEF_DIR)
  