* config/bfin/bfin.c (bfin_library_id_string): Remove.
(bfin_library_id): New variable.
(bfin_expand_prologue): Use bfin_library_id and bfin_lib_id_given
instead of bfin_library_id_string.
(bfin_handle_option): New function.
(override_options): Remove most code to deal with shared library IDs,
just check they aren't used without -mid-shared-library.
(TARGET_HANDLE_OPTION): Define.
* config/bfin/bfin.h (TARGET_OPTIONS): Delete macro.
* config/bfin/bfin.opt (mshared-library-id=): New.