Disallow using stlport by just adding /stlport//stlport

to sources.  This logic was trying to use non-free
usage requirements that are not supported, and can
potentially result in inconsistent builds.


[SVN r39646]

tools/build

@@ -1 +1 @@
-Subproject commit 8a9b29bf4bdaf2f7a485b811bec3df4d63f67fcc
+Subproject commit 2efa23a6a58da68fb39f63271348dd01a7862d95