Fix tarball for master

since the changes to the build system (eg. https://github.com/mono/mono/commit/e0e3f3cd4f2aad1f92aec1d53b00793541109c13), make dist would generate a tarball, that is broken.
You get errors because of missing System.Security.dll and System.Configuration.dll

The other issue is that the subdirectories in mcs/class/Facades are completely missing (caused by commit https://github.com/mono/mono/commit/8f51223150c1066255620b275a9908191cd27d1a)

This pull request fixes the problems, I am able to build from the tarball again.