nfscommon: Revert use of nfsstatsv1_p in nfs_commonkrpc.c

Commit 9d329bbc9aea converted a lot of accesses to nfsstatsv1
to use nfsstatsv1_p instead. However, the accesses in
nfs_commonkrpc.c are for client side and should not be
converted. This patch puts them back in the correct
pre-commit 9d329bbc9aea form.

MFC after: 3 months