[clang] [HLSL] Move `_init_resource_bindings` to entry point functions (PR #119311)

[Chris B via cfe-commits]

llvm-beanz wrote:

> You are correct @llvm-beanz, this change is not needed at all. Sorry for wasting your time!

Even a broken clock is right twice a day... me being the broken clock here 😄

It's never a waste to put something up to review if it helps us get to the right solution.

https://github.com/llvm/llvm-project/pull/119311