SUNRPC: Use unsigned index when looping over arrays

Clean up: Suppress a harmless compiler warning in the RPC server related
to array indices.

ARRAY_SIZE() returns a size_t, so use unsigned type for a loop index when
looping over arrays.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

net/sunrpc/svc.c

@@ -534,8 +534,9 @@ svc_init_buffer(struct svc_rqst *rqstp, unsigned int size)
 static void
 svc_release_buffer(struct svc_rqst *rqstp)
 {
-	int i;
-	for (i=0; i<ARRAY_SIZE(rqstp->rq_pages); i++)
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(rqstp->rq_pages); i++)
 		if (rqstp->rq_pages[i])
 			put_page(rqstp->rq_pages[i]);
 }