ihandle: Add FDH_ISUNLINKED
Add the FDH_ISUNLINKED functionality to ihandle. This lets the caller
know if the file for the underlying file descriptor has been deleted
out from under us. This is useful for sanity checks in some callers.
Change-Id: I59d4fffba853cfa1b900a08b7b43134c29bbf844
Reviewed-on: http://gerrit.openafs.org/8838
Reviewed-by: Chas Williams - CONTRACTOR <chas@cmf.nrl.navy.mil>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>