MSVC 8.0 does not produce manifest file when statically linking to runtime.

Make sure we only try to embed manifest in executable if it was created.

Patch from Alexey Pakhunov.


[SVN r32306]

tools/build

@@ -1 +1 @@
-Subproject commit c6e6875055e8ea7963b651c2ba236537083436e9
+Subproject commit 6585ab5128e55c6efa3bdcc62649ff6762347971