[X86] Use a range-based for loop (NFC) (#103519)

Author: kazutakahirata

llvm/lib/Target/X86/X86Subtarget.cpp

@@ -283,8 +283,8 @@ void X86Subtarget::initSubtargetFeatures(StringRef CPU, StringRef TuneCPU,
   SmallVector<StringRef, 9> FeaturesIn64BitOnly = {
       "egpr", "push2pop2", "ppx", "ndd", "ccmp", "nf", "cf", "zu", "uintr"};
   if (FullFS.find("-64bit-mode") != std::string::npos)
-    llvm::for_each(FeaturesIn64BitOnly,
-                   [&](StringRef F) { FullFS += ",-" + F.str(); });
+    for (StringRef F : FeaturesIn64BitOnly)
+      FullFS += ",-" + F.str();
 
   // Parse features string and set the CPU.
   ParseSubtargetFeatures(CPU, TuneCPU, FullFS);