linux-imx

nfsd: move some blocklayout code

Trivial reorganization, no change in behavior.  Move some code around,
pull some code out of block layoutcommit that will be useful for the
scsi layout.

[bfields@redhat.com: split off from "nfsd: add SCSI layout support"]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>