LU-8191 llite: convert functions to static

LU-8191 llite: convert functions to static

Static analysis shows that a number of functions
could be made static. This patch declares several
functions in llite static.

Also, conserve more * in comments.

Lustre-change: https://review.whamcloud.com/51441
Lustre-commit: a586a2bbc37879dc22382793d1704e7708b80887

Test-Parameters: trivial
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: Iafa3bb84de158e31b27b7784243bc15e78187f10
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/54613
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>