r13366: Add popt to the include path for examples/VFS. The modules themselves don't

r13366: Add popt to the include path for examples/VFS. The modules themselves don't
use that, but includes.h fails in environments where there's no system popt
around. As the modules don't need that anyway, porting the check whether to
use the system one or our own seems a bit overkill.

Thanks to Michael Adam <ma@SerNet.DE>.

Volker