secure: Rearrange Makefile SRCS to match upstream Makefile.in

[jlduran]

Summary

SRCS entries are kept in the same order and with the same line breaks as
upstream, to make comparison easier.

No functional change intended.

[jlduran]

Hopefully this revision stack helps facilitate adapting OpenSSH 10.0p2 changes, and the new sshd-auth binary.

[jlduran]

Match upstream Makefile.in as close as possible.

[emaste]

LGTM, with a couple of small notes you could incorporate

secure/libexec/sftp-server/Makefile

4–6

Spaces rendering strangely in Phab - maybe one line is spaces and one is a tab?

secure/usr.bin/scp/Makefile

5

We could move this line to ssh.mk to share it between scp and sftp.

secure/usr.bin/ssh-add/Makefile

5

This is fine, or we could add ${SKSRCS}

[jlduran]

secure/libexec/sftp-server/Makefile

4–6

They are both tabs. It should be a Phab quirk.

secure/usr.bin/scp/Makefile

5

That idea crossed my mind.
Note to self: If two or more files share the same options, move it to the common place.
Will do when committing.
Thank you!

secure/usr.bin/ssh-add/Makefile

5

This is done later in D49795.