ssh: Move XAUTH_PATH setting to ssh.mk

[emaste]

Summary

XAUTH_PATH is normally set (in the upstream build infrastructure) in
config.h.  We previously set it in ssh and sshd's Makefiles if LOCALBASE
is set, and over time have occasionally defined it in config.h.

Leave it unset in config.h and move the CFLAGS logic to to ssh.mk so
that it will be set when building all ssh libraries and programs but
still be set by LOCALBASE.

[emaste]

crypto/openssh/config.h

2018

Note that crypto/openssh/freebsd-configure.sh runs configure with --without-xauth so this is more consistent with the way we generate config.h.

secure/ssh.mk

12

Or ${LOCALBASE:U/usr/local}

[emaste]

Use /usr/local by default if LOCALBASE not set

[jlduran]

secure/ssh.mk

12

With this approach, LOCALBASE and XAUTH_PATH will always be defined (and therefore _PATH_XAUTH).
I guess this is what is desired.