CodeGen: Remove implicit ilist iterator conversions, NFC

Finish removing implicit ilist iterator conversions from LLVMCodeGen.
I'm sure there are lots more of these in lib/CodeGen/*/.

llvm-svn: 249915
diff --git a/llvm/lib/CodeGen/SpillPlacement.cpp b/llvm/lib/CodeGen/SpillPlacement.cpp
index afb63ff..d30cfc2 100644
--- a/llvm/lib/CodeGen/SpillPlacement.cpp
+++ b/llvm/lib/CodeGen/SpillPlacement.cpp
@@ -187,9 +187,9 @@
   BlockFrequencies.resize(mf.getNumBlockIDs());
   MBFI = &getAnalysis<MachineBlockFrequencyInfo>();
   setThreshold(MBFI->getEntryFreq());
-  for (MachineFunction::iterator I = mf.begin(), E = mf.end(); I != E; ++I) {
-    unsigned Num = I->getNumber();
-    BlockFrequencies[Num] = MBFI->getBlockFreq(I);
+  for (auto &I : mf) {
+    unsigned Num = I.getNumber();
+    BlockFrequencies[Num] = MBFI->getBlockFreq(&I);
   }
 
   // We never change the function.