Revert 'Fix a typo 'iff' => 'if''. iff is an abreviation of if and only if. See: http://en.wikipedia.org/wiki/If_and_only_if Commit 164766

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@164769 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaAccess.cpp b/lib/Sema/SemaAccess.cpp
index ddb5e4e..58b1a51 100644
--- a/lib/Sema/SemaAccess.cpp
+++ b/lib/Sema/SemaAccess.cpp
@@ -918,7 +918,7 @@
 ///     let AccessToBase = Merge(Access(B_i, B_{i+1}), ACAB(i+1)) in
 ///     if Accessible(B_i, AccessToBase) then public else AccessToBase
 ///
-/// B is an accessible base of N at R if ACAB(1) = public.
+/// B is an accessible base of N at R iff ACAB(1) = public.
 ///
 /// \param FinalAccess the access of the "final step", or AS_public if
 ///   there is no final step.