Tidy up comment.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@101357 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index afcf26f..4ac340d 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -1393,10 +1393,9 @@
 
   // Claim some arguments which clang supports automatically.
 
-  // -fpch-preprocess is used with gcc to add a special marker in the
-  // -output to include the PCH file. Clang's PTH solution is
-  // -completely transparent, so we do not need to deal with it at
-  // -all.
+  // -fpch-preprocess is used with gcc to add a special marker in the output to
+  // include the PCH file. Clang's PTH solution is completely transparent, so we
+  // do not need to deal with it at all.
   Args.ClaimAllArgs(options::OPT_fpch_preprocess);
 
   // Claim some arguments which clang doesn't support, but we don't