Blender Git Loki

Revert the changes for ccache and lld.

These were meant to be local changes & not pushed to the GSoC branch.
After discussion with the mentors, I'm adding this reverting commit.
Moreover, LLD for mach-o is not production ready & under development.
See [1] [2].

Now building the branch will not need any modifications.

[1]: https://reviews.llvm.org/D75382
[2]: http://clang-developers.42468.n3.nabble.com/Building-clang-on-OSX-td4064374.html#a4064378