Fix PE/COFF resource merging problems.  There were two issues:

  1. Strings (and then resource data) must follow immediately after
     the end of the tables.
  2. Units of resource data must be 8-byte aligned.

	PR ld/16807
	* peXXigen.c (struct rsrc_regions): New structure.
	(rsrc_print_resource_directory): Use new structure.  Include
	offset of directory in listing.
	(rsrc_print_resource_entry): Likewise.
	(rsrc_print_section): Likewise.
	(rsrc_count_entries): Do not increment sizeof_strings or
	sizeof_leaves.
	(rsrc_count_directory): Do not increment sizeof_tables.
	(rsrc_compute_region_sizes): New function.
	(rsrc_write_leaf): Maintain 8-byte alignment for resource data.
	(rsrc_process_section): Compute size of regions after merging
	entries.
Fix a problem building the ARM assembler for non-ELF based toolchains.

	* config/tc-arm.c (s_ltorg): Only create a mapping symbol for ELF
	based targets.