LU-13031 jobstats: store jobid in xattr when files are created

LU-13031 jobstats: store jobid in xattr when files are created

This change stores the jobid of the process that creates a file in an
extended attribute in the file's MDT inode, at file creation time.

The name of the xattr is determined by a new sysfs parameter
"mdt.*.job_xattr" so that the admin can choose a name that does
not conflict with other uses they may have for a given xattr.
The default value is "user.job". A value of "NONE" means that
the jobid will not be stored in the inode.

If the name is in the user namespace "user.", then the name portion
can be up to 7 alphanumeric characters long. The admin can choose
the trusted namespace to prevent users from modifying the value,
but only "trusted.job" is allowed in this namespace.

Allowing users to modify the contents of the xattr is helpful so
that the jobid can be preserved even when files are moved with tools
like `cp` or `rsync`, and when copied from one filesystem to another.

Lustre-change: https://review.whamcloud.com/50982
Lustre-commit: 23a2db28dcf1422a6a6da575e907fd257106d402

LU-13031 tests: skip sanity/test_205h,205i in interop

Skip sanity tests 205h and 205i when the MDS version is too old
to have the jobid xattr changes. Fix test 103a to not try to set
the job_xattr parameter when it does not exist.

Lustre-change: https://review.whamcloud.com/52095
Lustre-commit: a6df532162556028c2ab9b974989fc0cca68d4fe

Test-Parameters: testlist=sanity clientdistro=el8.8 clientjob=lustre-b_es-reviews clientbuildno=12634 env=ONLY=103
Signed-off-by: Thomas Bertschinger <bertschinger@lanl.gov>
Change-Id: Iad78a5ec6fbc4b761ff481141763bdd0cdcd0128
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/52195
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>