boards.cfg: move boards with invalid emails to Orphan

When I cc board maintainers, some of them result in
bounce mails.

It turned out the following do not work any more:
  Yuli Barcohen <yuli@arabellasw.com>
  Travis Sawyer <travis.sawyer@sandburst.com>
  Yusdi Santoso <yusdi_santoso@adaptec.com>
  David Updegraff <dave@cray.com>
  Sangmoon Kim <dogoil@etinsys.com>
  Anton Vorontsov <avorontsov@ru.mvista.com>
  Blackfin Team <u-boot-devel@blackfin.uclinux.org>
  Bluetechnix Tinyboards <bluetechnix@blackfin.uclinux.org>
  Andre Schwarz <andre.schwarz@matrix-vision.de>

For the blackfin boards where Sonic Zhang is also listed
as a maintainer, dead addresses should be simply dropped.

For all of the others, the status should be changed to "Orphan".

We have adopted the definition of "Orphan" as:
board is not actively maintained any more but still builds, and any
address associated with it is that of the last known maintainer(s)

Even though the emails do not work any more, they carry information.
We want to keep them.

Besides, Orphan boards have been collected at the bottom of boards.cfg.
(This is done when we run "tools/reformat.py")

Add separators to distinguish them from those which
were moved to Orphan 6 months ago.
I believe it will be helpful in future to find which boards are
old enough to be removed from the code base.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Detlev Zundel <dzu@denx.de>
Cc: Tom Rini <trini@ti.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>