lto-wrapper: Use vec<cl_decoded_option> data type.
gcc/ChangeLog:
* lto-wrapper.c (get_options_from_collect_gcc_options): Change
return type.
(append_option): Remove.
(find_option): Rework to use the vector type.
(remove_option): Remove.
(merge_and_complain): Use vectors for cl_decoded_option data
type arguments.
(append_compiler_options): Likewise.
(append_diag_options): Likewise.
(append_linker_options): Likewise.
(append_offload_options): Likewise.
(compile_offload_image): Likewise.
(compile_images_for_offload_targets): Likewise.
(find_and_merge_options): Likewise.
(run_gcc): Likewise.