LU-17370 utils: simplify lfs help text

LU-17370 utils: simplify lfs help text

Simplify help text for lfs getstripe and lfs setstripe.
Update corresponding man pages lfs-getstripe and lfs-setstripe.
On man pages make left side adjustment and disable hyphenation:
'.nh', '.ad l' to prevent hyphenation of keywords

Signed-off-by: Alexandre Ioffe <aioffe@ddn.com>
Test-Parameters: trivial
Change-Id: Iae9d3534230ee7d325fbeffd78b5c12632a4a161
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/53564
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>