NFSD: introduce netlink stubs

Generate stubs and uAPI for nfsd netlink protocol. For the moment,
the new protocol has one operation: rpc_status.

The generated header and source files are created by running:

  tools/net/ynl/ynl-regen.sh

Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

include/uapi/linux/nfsd_netlink.h

@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/nfsd.yaml */
+/* YNL-GEN uapi header */
+
+#ifndef _UAPI_LINUX_NFSD_H
+#define _UAPI_LINUX_NFSD_H
+
+#define NFSD_FAMILY_NAME	"nfsd"
+#define NFSD_FAMILY_VERSION	1
+
+enum {
+	NFSD_A_RPC_STATUS_XID = 1,
+	NFSD_A_RPC_STATUS_FLAGS,
+	NFSD_A_RPC_STATUS_PROG,
+	NFSD_A_RPC_STATUS_VERSION,
+	NFSD_A_RPC_STATUS_PROC,
+	NFSD_A_RPC_STATUS_SERVICE_TIME,
+	NFSD_A_RPC_STATUS_PAD,
+	NFSD_A_RPC_STATUS_SADDR4,
+	NFSD_A_RPC_STATUS_DADDR4,
+	NFSD_A_RPC_STATUS_SADDR6,
+	NFSD_A_RPC_STATUS_DADDR6,
+	NFSD_A_RPC_STATUS_SPORT,
+	NFSD_A_RPC_STATUS_DPORT,
+	NFSD_A_RPC_STATUS_COMPOUND_OPS,
+
+	__NFSD_A_RPC_STATUS_MAX,
+	NFSD_A_RPC_STATUS_MAX = (__NFSD_A_RPC_STATUS_MAX - 1)
+};
+
+enum {
+	NFSD_CMD_RPC_STATUS_GET = 1,
+
+	__NFSD_CMD_MAX,
+	NFSD_CMD_MAX = (__NFSD_CMD_MAX - 1)
+};
+
+#endif /* _UAPI_LINUX_NFSD_H */