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/CodeGen/CGExprAgg.cpp b/clang/lib/CodeGen/CGExprAgg.cpp
index e2871e3..6693ddd 100644
--- a/clang/lib/CodeGen/CGExprAgg.cpp
+++ b/clang/lib/CodeGen/CGExprAgg.cpp
@@ -746,7 +746,7 @@
     if (isToAtomic) {
       AggValueSlot valueDest = Dest;
       if (!valueDest.isIgnored() && CGF.CGM.isPaddedAtomicType(atomicType)) {
-        // Zero-initialize.  (Strictly speaking, we only need to intialize
+        // Zero-initialize.  (Strictly speaking, we only need to initialize
         // the padding at the end, but this is simpler.)
         if (!Dest.isZeroed())
           CGF.EmitNullInitialization(Dest.getAddress(), atomicType);