NFSv4: Specify the type of ACL to cache

When caching a NFSv4 ACL, we want to specify whether we are caching an
NFSv4.0 type acl, the NFSv4.1 dacl or the NFSv4.1 sacl.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>