This symbol is not used outside of nfs4proc.c, so marks it
static.

Fixes the following sparse warning:

fs/nfs/nfs4proc.c:4062:5: warning: no previous prototype for
‘nfs4_discover_trunking’ [-Wmissing-prototypes].

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
---
 fs/nfs/nfs4proc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index e6b49d6318bc..644ba8a02960 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -4059,7 +4059,7 @@ static int _nfs4_discover_trunking(struct nfs_server *server,
 	return status;
 }
 
-int nfs4_discover_trunking(struct nfs_server *server, struct nfs_fh *fhandle)
+static int nfs4_discover_trunking(struct nfs_server *server, struct nfs_fh *fhandle)
 {
 	struct nfs4_exception exception = {
 		.interruptible = true,
-- 
2.20.1.7.g153144c