linux-phytec-ti

nfsd4: stricter cred comparison for setclientid/exchange_id

The typical setclientid or exchange_id will probably be performed with a
credential that maps to either root or nobody, so comparing just uid's
is unlikely to be useful.  So, use everything else we can get our hands
on.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>