PNFS fix EACCESS on commit to DS handling

PNFS fix EACCESS on commit to DS handling

Commit fabbbee0eb0f "PNFS fix fallback to MDS if got error on
commit to DS" moved the pnfs_set_lo_fail() to unhandled errors
which was not correct and lead to a kernel oops on umount.

Instead, fix the original EACCESS on commit to DS error by
getting the new layout and re-doing the IO.

Fixes: fabbbee0eb0f ("PNFS fix fallback to MDS if got error on commit to DS")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Cc: stable@vger.kernel.org # v4.12
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>