roken: Import Windows allocator changes

roken: Import Windows allocator changes

Roken now supports using a single allocator across all of the objects
which include that roken library. Two additional objects are required
to support this, so add them to the list of symbols that we import.

Change-Id: If43537f06a6cdc6ea4dea278cdc1db1e6970f955
Reviewed-on: http://gerrit.openafs.org/7618
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>