In preparation for some updates to external/openssh to make it work with
BoringSSL, this change updates the code to a recent version. The current
version (5.9p1) is coming up on four years old now.

  * Confirmed that f5c67b47 matches
    OpenSSH 5.9p1 exactly (save for the removal of the scard
    subdirectory).

  * Downloaded openssh-6.8p1.tar.gz (SHA256:
    3ff64ce73ee124480b5bf767b9830d7d3c03bbcb6abe716b78f0192c37ce160e)
    and verified with PGP signature. (I've verified Damien's key in
    person previously.)

  * Applied changes between f5c67b47 and
    OpenSSH 5.9p1 to 6.8p1 and updated the build as best I can. The
    ugliest change is probably the duplication of umac.c to umac128.c
    because Android conditionally compiles that file twice. See the
    comment in those files.

Change-Id: I63cb07a8118afb5a377f116087a0882914cea486

Change-Id: I23324372188fa6ed3f93a32b84365f5df6367590

This may require changes to other code, such as fastbootd, which relies on this
service.  sshd is not currently, used, however, so this change will force any
such code to be changed.

Bug: 11594902
Change-Id: I07e52008290dab5825be2ad062cbe730fa7dff71

Change-Id: I0a1997bfa45966f619f9ec5ffaeb8f9be9f741e9
Signed-off-by: Mike Lockwood <lockwood@google.com>

Change-Id: I991b8d22c9904ed6ced33a096776f4f342af52a8
Signed-off-by: Mike Lockwood <lockwood@google.com>

Change-Id: I2571f00b4b6ba41b7795c8c78c58253e5d0205dd
Signed-off-by: Mike Lockwood <lockwood@google.com>

Change-Id: I8ebb99a5acc541716cfaab5b30bd8f7a86996977
Signed-off-by: Mike Lockwood <lockwood@google.com>