PR 868

PR 868
   * libbfd.c (bfd_realloc_or_free): New function.  Performs like
   bfd_realloc, but if the (re)allocation fails, the pointer is
   freed.
   * libbfd-in.h: Prototype.
   * libbfd.h: Regenerate.
   * bfdio.c (bfd_bwrite): Use the new function.
   (bfd_seek): Likewise.
   * bfdwin.c:(bfd_get_file_window): Likewise.
   * elf-strtab.c (_bfd_elf_strtab_add): Likewise.
   * elf32-ppc.c (ppc_elf_relax_section): Likewise.
   * elf32-xtensa.c (vsprintf_msg): Likewise.
   * mach-o.c (bfd_mach_o_core_fetch_environment): Likewise.
   * stabs.c (_bfd_link_seciton_stabs): Likewise.
   * vms-misc.c (_bfd_vms_get_record): Likewise.
   * vms-tir.c (check_section): Likewise.
   * vms.c (vms_new_section_hook): Likewise.
   * elf32-arm.c (elf32_arm_section_map_add): Check that the
   allocation of sec_data->map succeeded before using it.
   * elflink.c (elf_link_output_sym): Do not overwrite finfo->
   symshndxbuf until it is known that the reallocation succeeded.