sunrpc: move the close processing after do recvfrom method

sunrpc: "Move close processing to a single place"
(d7979ae4

) moved the
close processing before the recvfrom method. This may
cause the close processing never to execute. So this
patch moves it to the right place.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>