[llvm] [cmake] Move LLVM_ENABLE_PIC cmake option to HandleLLVMOptions.cmake (PR #84750)

[Saleem Abdulrasool via llvm-commits]

https://github.com/compnerd approved this pull request.

Given that this is just a shuffle, I think that it should be okay. This option definitely should be made available globally for the standalone builds. The questions it raises are around the default values, but I can understand the desire to make the behaviour of the shuffled code identical.

https://github.com/llvm/llvm-project/pull/84750