NFSv4: Place the GETATTR operation before the CLOSE

NFSv4: Place the GETATTR operation before the CLOSE

In order to benefit from the DENY share lock protection, we should
put the GETATTR operation before the CLOSE. Otherwise, we might race
with a Windows machine that thinks it is now safe to modify the file.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>