* lto-streamer-in.c (lto_get_builtin_tree): Fix handling of
target builtins.
* lto-streamer-out.c (lto_output_tree_pointers): Use sorry,
not gcc_unreachable.
(lto_output_builtin_tree): Sorry if the target does not support
streaming target builtins.
* config/rs6000/rs6000.c (TARGET_BUILTIN_DECL): Define.
(rs6000_builtin_decl): New function.
* config/i386/i386.c (TARGET_BUILTIN_DECL): Define.
(ix86_builtin_decl): New function.