systemd: bump version to 234

Other changes:
- Removed the following patches due to being merged upstream:
    - resolved-bugfix-of-null-pointer-p-question-dereferencing.patch
    - resolved-simplify-alloc-size-calculation.patch
    - resolved-do-not-allocate-packets-with-minimum-size.patch
- Updated the following patches to work with 234:
    - fix-getty-unit.patch
    - build-check-for-ln-relative.patch
    - fix-am-path-libgcrypt-no-found.patch
- Updated ordering of remaining patches.
- Reformatted remaining patches as git style patches.
- Updated Upstream-Status comment in "build-check-for-ln-relative.patch" to
  "Denied [No desire to support building on old distributions]"

Signed-off-by: Adam Duskett <aduskett@gmail.com>
Tested-by: Marcus Hoffmann <m.hoffmann@caretelsol.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>