PR ld/2723
* elflink.c (bfd_elf_final_link): Don't output section symbols
for special ELF sections.
ld/testsuite/
Update for removal of some section syms.
* elfcode.h (elf_slurp_symbol_table): Use bfd_elf_sym_name so that
canonical sections syms have a name.
gas/testsuite/
Update for changed section syms.
ld/testsuite/
Update for changed section syms.
ld-mmix/bpo-9.s, ld-mmix/bpo-19.d, ld-mmix/bpo-19m.d,
ld-mmix/bpo-10.s, ld-mmix/bpo-20.d, ld-mmix/bpo-20m.d: New tests
for on-demand global register allocation.
