More Tru64 fixes:

- add '-shared' for DLL compiles
- compile C files with the C compiler.


[SVN r32762]

tools/build

@@ -1 +1 @@
-Subproject commit d828779fbbe44b5ac85170921ab4c23b01d4245c
+Subproject commit 17d739240991c42c55f8647ef4324b4973043596