Improve dump of xdata/pdata on x86_64.

Improve dump of xdata/pdata on x86_64.

bfd/
2013-11-27  Tristan Gingold  <gingold@adacore.com>

	* pei-x86_64.c (pex_regs): Make it const.  Add comments.
	(pex64_get_runtime_function): Do not split UnwindData.
	(pex64_get_unwind_info): Extract the chain and the handler.
	(pex64_xdata_print_uwd_codes): Rewritten: do not reverse print
	the opcode, handle version 2, add consistency check, make the
	code host neutral.
	(pex64_dump_xdata): Change arguments to pass the section and its
	content.  Handle version 2, change output.
	(pex64_bfd_print_pdata): Add comments, load section for xdata.
	Avoid duplicate outputs.

include/coff
2013-11-27  Tristan Gingold  <gingold@adacore.com>

	* pe.h (struct pex64_runtime_function): Remove isChained.
	(UWOP_SAVE_XMM): Add comment.
	(struct pex64_unwind_info): Remove extra fields.