cmd/nm, cmd/objdump, cmd/pprof: disassembly is not supported on loong64

Contributors to the loong64 port are:
  Weining Lu <[email protected]>
  Lei Wang <[email protected]>
  Lingqin Gong <[email protected]>
  Xiaolin Zhao <[email protected]>
  Meidan Li <[email protected]>
  Xiaojuan Zhai <[email protected]>
  Qiyuan Pu <[email protected]>
  Guoqi Chen <[email protected]>

This port has been updated to Go 1.15.6:
  https://github.com/loongson/go

Updates #46229

Change-Id: Ic96e4f0c46d9a6b8cd020e899f32c40681daf9c5
Reviewed-on: https://go-review.googlesource.com/c/go/+/342323
Run-TryBot: Ian Lance Taylor <[email protected]>
Reviewed-by: David Chase <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>
Auto-Submit: Ian Lance Taylor <[email protected]>

Author: XiaodongLoong

src/cmd/nm/nm_cgo_test.go

@@ -24,7 +24,7 @@ func canInternalLink() bool {
 		}
 	case "linux":
 		switch runtime.GOARCH {
-		case "arm64", "mips64", "mips64le", "mips", "mipsle", "ppc64", "ppc64le", "riscv64":
+		case "arm64", "loong64", "mips64", "mips64le", "mips", "mipsle", "ppc64", "ppc64le", "riscv64":
 			return false
 		}
 	case "openbsd":

src/cmd/objdump/objdump_test.go

@@ -107,6 +107,8 @@ var ppcGnuNeed = []string{
 
 func mustHaveDisasm(t *testing.T) {
 	switch runtime.GOARCH {
+	case "loong64":
+		t.Skipf("skipping on %s", runtime.GOARCH)
 	case "mips", "mipsle", "mips64", "mips64le":
 		t.Skipf("skipping on %s, issue 12559", runtime.GOARCH)
 	case "riscv64":

src/cmd/pprof/pprof_test.go

@@ -72,6 +72,8 @@ func mustHaveCPUProfiling(t *testing.T) {
 
 func mustHaveDisasm(t *testing.T) {
 	switch runtime.GOARCH {
+	case "loong64":
+		t.Skipf("skipping on %s.", runtime.GOARCH)
 	case "mips", "mipsle", "mips64", "mips64le":
 		t.Skipf("skipping on %s, issue 12559", runtime.GOARCH)
 	case "riscv64":