sunrpc: properly type pc_release callbacks

Drop the p and resp arguments as they are always NULL or can trivially
be derived from the rqstp argument.  With that all functions now have the
same prototype, and we can remove the unsafe casting to kxdrproc_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 9533545..4611cb7 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1287,12 +1287,12 @@
 		if (*statp == rpc_drop_reply ||
 		    test_bit(RQ_DROPME, &rqstp->rq_flags)) {
 			if (procp->pc_release)
-				procp->pc_release(rqstp, NULL, rqstp->rq_resp);
+				procp->pc_release(rqstp);
 			goto dropit;
 		}
 		if (*statp == rpc_autherr_badcred) {
 			if (procp->pc_release)
-				procp->pc_release(rqstp, NULL, rqstp->rq_resp);
+				procp->pc_release(rqstp);
 			goto err_bad_auth;
 		}
 		if (*statp == rpc_success &&
@@ -1307,7 +1307,7 @@
 		if (!versp->vs_dispatch(rqstp, statp)) {
 			/* Release reply info */
 			if (procp->pc_release)
-				procp->pc_release(rqstp, NULL, rqstp->rq_resp);
+				procp->pc_release(rqstp);
 			goto dropit;
 		}
 	}
@@ -1318,7 +1318,7 @@
 
 	/* Release reply info */
 	if (procp->pc_release)
-		procp->pc_release(rqstp, NULL, rqstp->rq_resp);
+		procp->pc_release(rqstp);
 
 	if (procp->pc_encode == NULL)
 		goto dropit;