cmd/objdump: disable TestDisasm.* on arm64

ARM64 doesn't have disassembler yet.

Change-Id: I016fa013b5ff50dc49d38ade42351b79be023d80
Reviewed-on: https://go-review.googlesource.com/7149Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

src/cmd/objdump/objdump_test.go

@@ -108,6 +108,8 @@ func TestDisasm(t *testing.T) {
 	switch runtime.GOARCH {
 	case "ppc64", "ppc64le":
 		t.Skipf("skipping on %s, issue 9039", runtime.GOARCH)
+	case "arm64":
+		t.Skipf("skipping on %s, issue 10106", runtime.GOARCH)
 	}
 	testDisasm(t)
 }
@@ -120,6 +122,8 @@ func TestDisasmExtld(t *testing.T) {
 	switch runtime.GOARCH {
 	case "ppc64", "ppc64le":
 		t.Skipf("skipping on %s, no support for external linking, issue 9038", runtime.GOARCH)
+	case "arm64":
+		t.Skipf("skipping on %s, issue 10106", runtime.GOARCH)
 	}
 	testDisasm(t, "-ldflags=-linkmode=external")
 }