nfs4_acls: Use correct owner information for ACL after owner change

nfs4_acls: Use correct owner information for ACL after owner change

After a chown, the cached stat data is obviously no longer valid. The
code in smb_set_nt_acl_nfs4 checked the file correctly, but did only use
a local buffer for the stat data. So later checks of the stat buffer
under the fsp->fsp_name->st would still see the old information.

Fix this by removing the local stat buffer and always update the one
under fsp->fsp_name->st.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14032

Signed-off-by: Christof Schmitt <cs@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>