[ELF] Print the .type assembly directive correctly for STT_NOTYPE

[olista01]

Summary

The llvm assembly parser and gas both accept "@notype" in the .type
assembly directive, but we were printing it as "@no_type", which isn't
accepted by either assembler.

[olista01]

Add a triple to the test.

[peter.smith]

LGTM. I can confirm that gas uses notype and that the other .type values also match those in gas.

lib/MC/MCAsmStreamer.cpp

case MCSA_ELF_TypeGnuUniqueObject:  /// .type _foo, @gnu_unique_object
     OS << ',' << ((MAI->getCommentString()[0] != '@') ? '@' : '%');
     switch (Attribute) {
     default: return false;
     case MCSA_ELF_TypeFunction:    OS << "function"; break;
     case MCSA_ELF_TypeIndFunction: OS << "gnu_indirect_function"; break;
     case MCSA_ELF_TypeObject:      OS << "object"; break;
     case MCSA_ELF_TypeTLS:         OS << "tls_object"; break;
     case MCSA_ELF_TypeCommon:      OS << "common"; break;
-    case MCSA_ELF_TypeNoType:      OS << "no_type"; break;
+    case MCSA_ELF_TypeNoType:      OS << "notype"; break;
     case MCSA_ELF_TypeGnuUniqueObject: OS << "gnu_unique_object"; break;
     }
     EmitEOL();
     return true;
   case MCSA_Global: // .globl/.global
     OS << MAI->getGlobalDirective();
     break;
   case MCSA_Hidden:         OS << "\t.hidden\t";          break;

test/MC/ARM/type-directive-print.ll

+; RUN: llc < %s | FileCheck %s
+
+module asm ".type test_notype, @notype"
+module asm ".type test_function, @function"
+module asm ".type test_object, @object"
+module asm ".type test_common, @common"
+module asm ".type test_tls_object, @tls_object"
+module asm ".type test_gnu_indirect_function, @gnu_indirect_function"
+module asm ".type test_gnu_unique_object, @gnu_unique_object"
+
+; CHECK: .type test_notype,@notype
+; CHECK: .type test_function,@function
+; CHECK: .type test_object,@object
+; CHECK: .type test_common,@common
+; CHECK: .type test_tls_object,@tls_object
+; CHECK: .type test_gnu_indirect_function,@gnu_indirect_function
+; CHECK: .type test_gnu_unique_object,@gnu_unique_object