We were failing to close on an error path, resulting in a leak of struct files
which could take a v4 server down fairly quickly....  So call
nfs4_close_delegation instead of just open-coding parts of it.

Simplify the cleanup on delegation failure while we're at it.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>