nfsd: Fix a file leak on nfsd4_layout_setlease failure

If nfsd4_layout_setlease fails, nfsd will not put ls->ls_file.

Fix commit c5c707f9 "nfsd: implement pNFS layout recalls".
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfs4layouts.c

@@ -212,6 +212,7 @@ nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
 	BUG_ON(!ls->ls_file);
 
 	if (nfsd4_layout_setlease(ls)) {
+		fput(ls->ls_file);
 		put_nfs4_file(fp);
 		kmem_cache_free(nfs4_layout_stateid_cache, ls);
 		return NULL;