LU-14291 lustre: clean up lustre_eacl.h and make server-only

LU-14291 lustre: clean up lustre_eacl.h and make server-only

lustre_eacl.h contains a number of declarations that are never used:
remove them.

The declarations which are used are only needed on server-side files,
so remove the #include from elsewhere.

As obdclass/acl.c is only built server-side, remove the
 #ifdef HAVE_SERVER_SUPPORT
in the file.

Test-Parameters: trivial
Signed-off-by: Mr NeilBrown <neilb@suse.de>
Change-Id: If1a3d908bf8357041c38ab9d335efa1e051cef16
Reviewed-on: https://review.whamcloud.com/41126
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>