nfsd4: Remove unneeded semicolon

Fixes coccicheck warning:

fs/nfsd/nfs4state.c:3376:2-3: Unneeded semicolon
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfs4state.c

@@ -3422,7 +3422,7 @@ static __be32 nfsd4_map_bcts_dir(u32 *dir)
 	case NFS4_CDFC4_BACK_OR_BOTH:
 		*dir = NFS4_CDFC4_BOTH;
 		return nfs_ok;
-	};
+	}
 	return nfserr_inval;
 }