Fix typos in clang

Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:

  archtype
  cas
  classs
  checkk
  compres
  definit
  frome
  iff
  inteval
  ith
  lod
  methode
  nd
  optin
  ot
  pres
  statics
  te
  thru

Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)

Differential revision: https://reviews.llvm.org/D44188

llvm-svn: 329399
diff --git a/clang/lib/Analysis/ThreadSafetyCommon.cpp b/clang/lib/Analysis/ThreadSafetyCommon.cpp
index 1376a89..07e3a75 100644
--- a/clang/lib/Analysis/ThreadSafetyCommon.cpp
+++ b/clang/lib/Analysis/ThreadSafetyCommon.cpp
@@ -817,7 +817,7 @@
 }
 
 void SExprBuilder::enterCFGBlock(const CFGBlock *B) {
-  // Intialize TIL basic block and add it to the CFG.
+  // Initialize TIL basic block and add it to the CFG.
   CurrentBB = lookupBlock(B);
   CurrentBB->reservePredecessors(B->pred_size());
   Scfg->add(CurrentBB);
@@ -892,7 +892,7 @@
     til::BasicBlock *BB1 = *It ? lookupBlock(*It) : nullptr;
     ++It;
     til::BasicBlock *BB2 = *It ? lookupBlock(*It) : nullptr;
-    // FIXME: make sure these arent' critical edges.
+    // FIXME: make sure these aren't critical edges.
     auto *Tm = new (Arena) til::Branch(C, BB1, BB2);
     CurrentBB->setTerminator(Tm);
   }