Merge branch 'hardlink' of https://github.com/rudimeier/util-linux into hardlink

Merge branch 'hardlink' of https://github.com/rudimeier/util-linux into hardlink

* 'hardlink' of https://github.com/rudimeier/util-linux: (25 commits)
  hardlink: add first simple tests
  hardlink: util-linux usage
  hardlink: fix compiler warnings
  hardlink: style indentations and license header
  hardlink: enable build with and without pcre2
  fixes for the fixes
  temporal fix before re-patch (updates from Fedora repo)
  Update hardlink.1
  Fixed version number, added changelog about Todd Lewis' patch
  exclude files via pcre
  Fixed 32 bit build with gcc7 (RH Bugzilla ID 1422989)
  spec file reflects the atomic hardlinking patch; removed cleaning buildroot (redundant); update FSF address at .c source file
  Revert "spec file reflects the atomic hardlinking patch; removed cleaning buildroot (redundant); current FSF address at .c source file"
  spec file reflects the atomic hardlinking patch; removed cleaning buildroot (redundant); current FSF address at .c source file
  Mention -f option in the man page
  do not allow to hardlink files across filesystems by default (#786719) (use -f option to override)
  fix possible buffer overflows, integer overflows, update man page
  fix URL and remove mmap() (#676962, #672917)
  - update docs to describe highest verbosity -vv option (#210816) - use dist Resolves: 210816
  mostly spec cleanup
  ...