SPECS: openssh: Align optional build dependencies

[Jingwiw]

Changes

• Drop the unused --with-systemd configure option and the unused pkgconfig(systemd) build dependency.

  OpenSSH 10.3p1 enables systemd notification on Linux directly and implements it without linking libsystemd.

  Source: configure.ac

  AC_DEFINE([SYSTEMD_NOTIFY], [1], [Have sshd notify systemd on start/reload])

  Source: openbsd-compat/port-linux.c

  #ifdef SYSTEMD_NOTIFY
  
  static void
  ssh_systemd_notify(const char *fmt, ...)
  {
      ...
      if ((path = getenv("NOTIFY_SOCKET")) == NULL || strlen(path) == 0)
          return;
      ...
      if ((fd = socket(PF_UNIX, SOCK_DGRAM, 0)) == -1) {
          ...
      }
      ...
  }

  The package still keeps systemd-rpm-macros, because the spec installs systemd units and uses systemd scriptlet macros.

• Make the FIDO2 builtin support follow the existing %bcond fido2.

  Upstream has a dedicated switch for builtin U2F/FIDO support, and the builtin path probes libfido2.

  Source: configure.ac

  AC_ARG_WITH([security-key-builtin],
      [  --with-security-key-builtin include builtin U2F/FIDO support],
      [ enable_sk_internal=$withval ]
  )

  Source: configure.ac

  if test "x$enable_sk" = "xyes" -a "x$enable_sk_internal" != "xno" ; then
      ...
      if "$PKGCONFIG" libfido2; then
          ...
      fi
      ...
      AC_CHECK_HEADER([fido.h], [],
          [ fido2_error="missing fido.h from libfido2" ])

• Fix the Kerberos BuildRequires guard to use the actual %bcond kerberos5.

• Keep Linux audit BuildRequires scoped to the SELinux build path that enables it.

  The spec only passes --with-audit=linux inside %if %{with selinux}, so the audit build dependency belongs under the same guard.

  Source: configure.ac

  AC_ARG_WITH([audit],
      [  --with-audit=module     Enable audit support (modules=debug,bsm,linux)],
      ...
      linux)
          ...
          AC_CHECK_HEADERS([libaudit.h])
          SSHDLIBS="$SSHDLIBS -laudit"
          AC_DEFINE([USE_LINUX_AUDIT], [1], [Use Linux audit module])

• Drop Requires: pkgconfig(audit) because pkgconfig dependencies are development interfaces, not runtime package requirements.

• Use %autochangelog directly, matching the current spec style.

AIGC Declaration: CodeX with gpt5.5 was used as coding agent.

Signed-off-by: Jingwiw wangjingwei@iscas.ac.cn