bos: do not assume fs just if dafs bnode is stopped
If dafs is configured but stopped, 'bos salvage <fs> <vicep>
-forceDAFS' will fail with:
bos: failed to get instance info for 'fs' (no such entity)
bos: shutting down 'fs'.
bos: can't stop 'fs' (no such entity)
This is due to incomplete logic in IsDAFS, introduced with commit
e46f10a0a0a930f318833a8a86b10c19744160c1 'bos: Do not assume DAFS just
if DAFS bnode exists'
Add logic to IsDAFS to work correctly when dafs is configured but
stopped.
Change-Id: I50f8209180536d25e68c0ad6fb826202d8f27ce7
Reviewed-on: https://gerrit.openafs.org/14382
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>