misc/cgo/test: skip test18146 on mips{,64}

Change-Id: I724f4443fc10a6ee0d027a9533f07aba39455cfa
Reviewed-on: https://go-review.googlesource.com/34312Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

misc/cgo/test/issue18146.go

@@ -26,6 +26,10 @@ func test18146(t *testing.T) {
 		t.Skipf("skipping flaky test on %s; see golang.org/issue/18202", runtime.GOOS)
 	}
 
+	if runtime.GOARCH == "mips" || runtime.GOARCH == "mips64" {
+		t.Skipf("skipping on %s", runtime.GOARCH)
+	}
+
 	attempts := 1000
 	threads := 4