commit 6404ab99
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Wed Aug 8 21:00:04 2018 -0700

    Convert .note.gnu.property section between ELF32 and ELF64

updated bfd_convert_section_size and bfd_convert_section_contents
in bfd.c to call _bfd_elf_convert_gnu_property_size and
_bfd_elf_convert_gnu_properties, which are defined in elf-properties.c.
It led to

bfd.c:2484: undefined reference to `_bfd_elf_convert_gnu_property_size'

for non-ELF targets.  Since elf-properties.c is a generic implementation
and doesn't reference any ELF specific functions directly, this patch
moves elf-properties.lo BFD32_LIBS.

Tested for many ELF and non-ELF targets.

	PR binutils/23494
	* Makefile.am (BFD32_LIBS): Add elf-properties.lo.
	(BFD32_LIBS_CFILES): Add elf-properties.c.
	(BFD32_BACKENDS): Remove elf-properties.lo.
	(BFD32_BACKENDS_CFILES): Remove elf-properties.c.
	* configure.ac (elf): Remove elf-properties.lo.
	* Makefile.in: Regenerated.
	* configure: Likewise.