* ld-elf/eh1.d: Add explicit --64 to as options, and explicit
-melf_x86_64 and -Ttext to ld options, so we don't assume every
x86_64-*-* target uses --64 (vs --x32) by default or has the
same address space layout.
* ld-elf/eh2.d: Likewise.
* ld-elf/eh3.d: Likewise.
* ld-elf/eh4.d: Likewise.
* ld-elf/elf.exp: For target *-*-nacl*, use options_regsub(ld) to
map -melf_x86_64 to -melf_x86_64_nacl.
* elf-eh-frame.c (skip_cfa_op): Fix handling of DW_CFA_advance_loc.
Handle DW_CFA_{remember,restore}_state, DW_CFA_GNU_window_save,
DW_CFA_val_{offset{,_sf},expression}.
(skip_non_nops): Record number of DW_CFA_set_loc ops.
(_bfd_elf_discard_section_eh_frame): Require skip_non_nops recognizes
all ops. If there are any DW_CFA_set_loc ops and they are pcrel
or going to be pcrel, compute set_loc array.
(_bfd_elf_eh_frame_section_offset): If make_relative, kill relocations
against DW_CFA_set_loc operands.
(_bfd_elf_write_section_eh_frame): Handle DW_CFA_set_loc adjusting.
* ld-elf/eh4.d: New test.
* ld-elf/eh4.s: New file.
* ld-elf/eh4a.s: New file.
