buildroot

elfutils: bump version to 0.166

- Remove 0001-argp-support.patch since it's already included upstream:
  https://git.fedorahosted.org/cgit/elfutils.git/commit/?id=1ab3c2befeedf5bd891cfbe17cfef79c06e5079a

- Tweak patches for this new version:
  - 0002-disable-progs.patch
  - 0003-fts.patch
  - 0004-disable-po.patch
  - 0005-really-make-werror-conditional-to-build-werror.patch

- Remove 0007-Allow-disabling-symbol-versioning-at-configure-t since
  it's already included upstream:
  https://git.fedorahosted.org/cgit/elfutils.git/commit/?id=bafacacaf7659a4933604662daba26a480b29a8d

- Remove portability patch since it's no longer needed. I have asked
  Mark Wielaard regarding this topic given the portability patch looks
  been discontinued since 0.163 and he replied the following:
  - "I believe it is no longer needed. At least not on any platform I
     am actively maintaining. See also this discussion from last year:
     https://lists.fedorahosted.org/pipermail/elfutils-devel/2015-May/004825.html"

- Add zlib dependency since it's now mandatory:
  configure: error: zlib not found but is required

Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>