dup_common fields.
(setup_sections): Use som_subspace_dictionary_record struct instead
subspace_dictionary_record. Set SEC_LINK_ONCE if subspace is
is_comdat, is_common or dup_common.
(som_prep_headers): Use som_subspace_dictionary_record struct. Set
is_comdat, is_common and dup_common in section subspace_dict from
copy_data.
(som_begin_writing): Use som_subspace_dictionary_record struct.
(som_finish_writing): Likewise.
(som_bfd_derive_misc_symbol_info): Add support to set is_comdat,
is_common and dup_common flags in info for symbol. Add comment
regarding linker support for these fields. Slightly reorganize
function.
(som_build_and_write_symbol_table): Set is_comdat, is_common and
dup_common fields in symbol table from symbol info.
(bfd_som_set_subsection_attributes): Add comdat, common and dup_common
arguments. Set corresponding fields in copy_data. Change all callers.
(som_bfd_ar_write_symbol_stuff): Set dup_common flag in library
symbol table.
(som_vec): Add SEC_LINK_ONCE to applicable section flags.
* som.h (som_subspace_dictionary_record): Define.
(som_copyable_section_data_struct): Add is_comdat, is_common and
dup_common fields.
(som_section_data_struct): Use som_subspace_dictionary_record struct
instead of subspace_dictionary_record.
(bfd_boolean bfd_som_set_subsection_attributes): Adjust prototype.
* config/obj-som.c (obj_som_init_stab_section): Add new arguments in
call to obj_set_subsection_attributes.
(obj_som_init_stab_section): Likewise.
* config/tc-hppa.c (default_subspace_dict): Add comdat field.
(pa_def_subspaces): Provide comdat default.
(pa_subspace): Handle new "comdat" parameter. Set SEC_LINK_ONCE and
not SEC_IS_COMMON if section is comdat, common or dup_common. Update
calls to create_new_subspace and update_subspace to pass comdat flag.
(create_new_subspace, update_subspace): Add new comdat argument. Use
it in calls to obj_set_subsection_attributes.
* doc/c-hppa.texi (.subspa, .nsubspa): Document new comdat parameter
and use of comdat, common and dup_comm parameters.