[x86][MemFold] Fix anon namespace in header

[fdeazeve]

Summary

D142084 moved an enumeration inside a header from the llvm namespace
into an anon namespace. Some of the bots started failing as a result.

[fdeazeve]

In the interest of time and since this is low risk, I'll go ahead and merge this, but please let me know if you have any concerns.

llvm/include/llvm/Support/X86FoldTablesUtils.h

 //===-- X86FoldTablesUtils.h ------------------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_SUPPORT_X86FOLDTABLESUTILS_H
 #define LLVM_SUPPORT_X86FOLDTABLESUTILS_H
 
-namespace {
+namespace llvm {
 enum {
   // Select which memory operand is being unfolded.
   // (stored in bits 0 - 2)
   TB_INDEX_0    = 0,
   TB_INDEX_1    = 1,
   TB_INDEX_2    = 2,
   TB_INDEX_3    = 3,
   TB_INDEX_4    = 4,
enum {
   TB_BCAST_D    =   0 << TB_BCAST_TYPE_SHIFT,
   TB_BCAST_Q    =   1 << TB_BCAST_TYPE_SHIFT,
   TB_BCAST_SS   =   2 << TB_BCAST_TYPE_SHIFT,
   TB_BCAST_SD   =   3 << TB_BCAST_TYPE_SHIFT,
   TB_BCAST_MASK = 0x3 << TB_BCAST_TYPE_SHIFT,
 
   // Unused bits 14-15
 };
-}
-#endif // LLVM_SUPPORT_X86FOLDTABLESUTILS_H
+} // namespace llvm
+#endif // LLVM_SUPPORT_X86FOLDTABLESUTILS_H