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/tools/scan-build-py/libscanbuild/analyze.py b/clang/tools/scan-build-py/libscanbuild/analyze.py
index 3c93b11..5a7cc20 100644
--- a/clang/tools/scan-build-py/libscanbuild/analyze.py
+++ b/clang/tools/scan-build-py/libscanbuild/analyze.py
@@ -94,7 +94,7 @@
     When static analyzer run against project configure step, it should be
     silent and no need to run the analyzer or generate report.
 
-    To run `scan-build` against the configure step might be neccessary,
+    To run `scan-build` against the configure step might be necessary,
     when compiler wrappers are used. That's the moment when build setup
     check the compiler and capture the location for the build process. """
 
@@ -437,7 +437,7 @@
     of the compilation database.
 
     This complex task is decomposed into smaller methods which are calling
-    each other in chain. If the analyzis is not possibe the given method
+    each other in chain. If the analyzis is not possible the given method
     just return and break the chain.
 
     The passed parameter is a python dictionary. Each method first check