* coffread.c (coff_symfile_init): Use set_objfile_data.
(coff_symfile_read): Use DBX_SYMFILE_INFO.
* dbxread.c (dbx_objfile_data_key): New global.
(dbx_symfile_init): Use set_objfile_data.
(dbx_symfile_finish): Don't free deprecated_sym_stab_info.
(dbx_free_symfile_info): New function.
(coffstab_build_psymtabs, elfstab_build_psymtabs): Use
DBX_SYMFILE_INFO.
(stabsect_build_psymtabs): Use set_objfile_data.
(_initialize_dbxreadb): Initialize dbx_objfile_data_key.
* elfread.c (elf_symtab_read): Use DBX_SYMFILE_INFO,
set_objfile_data.
(free_elfinfo): Use DBX_SYMFILE_INFO.
(elf_symfile_finish): Don't free deprecated_sym_stab_info.
(elfstab_offset_sections): Use DBX_SYMFILE_INFO.
* gdb-stabs.h (dbx_objfile_data_key): Declare.
(DBX_SYMFILE_INFO): Rewrite to use objfile_data.
* objfiles.h (struct objfile) <deprecated_sym_stab_info>: Remove.
* somread.c (som_symfile_finish): Don't free
deprecated_sym_stab_info.