NFSv4: Rename nfs4_copy_stateid()

It is really a function for selecting the correct stateid to use in a
read or write situation.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index b0647b3..f181c70 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1922,7 +1922,7 @@
 	if (nfs4_copy_delegation_stateid(&arg.stateid, inode)) {
 		/* Use that stateid */
 	} else if (state != NULL) {
-		nfs4_copy_stateid(&arg.stateid, state, current->files, current->tgid);
+		nfs4_select_rw_stateid(&arg.stateid, state, current->files, current->tgid);
 	} else
 		memcpy(&arg.stateid, &zero_stateid, sizeof(arg.stateid));