Document vos listaddrs -host and -uuid

Document vos listaddrs -host and -uuid

Document the -host and -uuid flags to vos listaddrs.  They were mentioned
in the SYNOPSIS, but not in the OPTIONS section of the manual page.

Change-Id: I96e6b67b7239d9455060fd0c76b8d44f41a010a2
Reviewed-on: http://gerrit.openafs.org/2083
Reviewed-by: Russ Allbery <rra@stanford.edu>
Tested-by: Russ Allbery <rra@stanford.edu>