fix(git): add vendor in .gitignore

vendor/golang.org/x/sys/cpu/cpu_ppc64x.go

@@ -1,17 +0,0 @@
-// Copyright 2020 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build ppc64 || ppc64le
-// +build ppc64 ppc64le
-
-package cpu
-
-const cacheLineSize = 128
-
-func initOptions() {
-	options = []option{
-		{Name: "darn", Feature: &PPC64.HasDARN},
-		{Name: "scv", Feature: &PPC64.HasSCV},
-	}
-}