[PATCH v3 1/5] d3dcompiler: Rename ID3D11ShaderReflection functions to d3d11_... from d3dcompiler_...

[Matteo Bruni]

First of all, sorry for the huge delay.

The patch is a bit awkward in that it's basically just style cleanup
and those are generally frowned upon. Also maybe we don't want to use
separate methods for d3d11 and d3d12 (more on that in reply to the
next patch).
It is a big cleanup though and I don't really want to waste your time
reworking it...