[CIR] Address Space support for GlobalOps (#179082)
Related: https://github.com/llvm/llvm-project/issues/179278,
https://github.com/llvm/llvm-project/issues/160386
Extends cir.global to accept address space attributes. Globals can now
specify either `target_address_space(N)` or
`lang_address_space(offload_*)`. Address spaces are also preserved
throughout get_global ops.
