LU-8955 ptlrpc: manage SELinux policy info for metadata ops

LU-8955 ptlrpc: manage SELinux policy info for metadata ops

Add SELinux policy info for following metedata operations:
- create
- open
- unlink
- rename
- getxattr
- setxattr
- setattr
- getattr
- symlink
- hardlink

On server side, get SELinux policy info from nodemap and compare
it with the one received from client.

Test-Parameters: serverbuildno=62488 serverjob=lustre-reviews testlist=sanity,sanity-selinux clientselinux
Test-Parameters: clientbuildno=4033 clientjob=lustre-reviews-patchless testlist=sanity,sanity-selinux clientselinux
Signed-off-by: Sebastien Buisson <sbuisson@ddn.com>
Change-Id: I16493d7c5713180fb065623b735d7348fc3f9140
Reviewed-on: https://review.whamcloud.com/24424
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Reviewed-by: Li Dongyang <dongyangli@ddn.com>
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>