NFSD: Only reinitilize the recall_lru list under the recall lock

unhash_delegation() will grab the recall lock before calling
list_del_init() in each of these places.  This patch removes the
redundant calls.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>