nfs_readpage_release() causes an oops while accessing a file with NFS
debugging turned on (echo 32767 > /proc/sys/sunrpc/nfs_debug) and a kernel
built with CONFIG_DEBUG_SLAB.

This patch moves the debugging statement above nfs_release_request() to
avoid accessing freed memory.
Signed-off-by: Nick Wilson <njw@osdl.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>