LU-14442 utils: [-r|-w] options for get/list_param

LU-14442 utils: [-r|-w] options for get/list_param

New [--readable|-r] and [--writable|-w] options have been added for
get_param and list_param that will only print parameters with the
specified permissions.
This is useful to find tunable parameters, or avoid write-only
parameters or statistics.

Signed-off-by: Frederick Dilger <fdilger@whamcloud.com>
Change-Id: I00fca8f354733c9ee6d75c60e39121c12068a2a4
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/55665
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>