[gn build] Port da315a3

Author: llvmgnsyncbot

llvm/utils/gn/secondary/bolt/lib/Core/BUILD.gn

@@ -36,6 +36,7 @@ static_library("Core") {
     "GDBIndex.cpp",
     "HashUtilities.cpp",
     "JumpTable.cpp",
+    "MCInstUtils.cpp",
     "MCPlusBuilder.cpp",
     "ParallelUtilities.cpp",
     "Relocation.cpp",