LU-10507 tests: use {save,restore}_layout() in test

LU-10507 tests: use {save,restore}_layout() in test

Revised test cases sanity:test_{27A,65i,65j,65m,406}(),
sanity-pfl:test_10() to use new interfaces to save and restore
layout.

This patch is back-ported from the following one:
Lustre-commit: 7b980e101e172d7d8b43a0db2dcaabc8c8c6c855
Lustre-change: https://review.whamcloud.com/30858

Test-Parameters: trivial testlist=sanity-pfl,sanity

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Change-Id: I11f4e5dcd486d4f7d08666c462d056041e125365
Reviewed-on: https://review.whamcloud.com/34159
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: James Nunez <jnunez@whamcloud.com>