Fix typo 'typdefs', from Nikola Smiljanic

llvm-svn: 146894

clang/docs/InternalsManual.html

@@ -928,7 +928,7 @@ typedef for foo.
 <p>Representing types like this is great for diagnostics, because the
 user-specified type is always immediately available.  There are two problems
 with this: first, various semantic checks need to make judgements about the
-<em>actual structure</em> of a type, ignoring typdefs.  Second, we need an
+<em>actual structure</em> of a type, ignoring typedefs.  Second, we need an
 efficient way to query whether two types are structurally identical to each
 other, ignoring typedefs.  The solution to both of these problems is the idea of
 canonical types.</p>