LU-12637 kernel: RHEL 8.1 server support

LU-12637 kernel: RHEL 8.1 server support

This patch makes changes to support RHEL 8.1 release with
kernel 4.18.0-147.3.1.el8_1 for Lustre server.

Test-Parameters: trivial \
envdefinitions=SANITY_EXCEPT="411 812b" \
clientdistro=el8.1 serverdistro=el8.1 \
testlist=sanity

Change-Id: Iee6ae3dc20c62caaac1d740b14c5877ff7bfb4d5
Signed-off-by: Jian Yu <yujian@whamcloud.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/36968
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Reviewed-by: Yang Sheng <ys@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>