[LLVM][NewPM] Add a C API for setting the PassBuilder AA pipeline. (#102482)
This PR adds a field to the pass builder options struct, `AAPipeline`,
exposed through a C API `LLVMPassBuilderOptionsSetAAPipeline`, that is
used to set an alias analysis pipeline to be used in stead of the
default one.
x-ref https://discourse.llvm.org/t/newpm-c-api-questions/80598