[clang] [CIR] Upstream initial attribute support (PR #121069)

[David Olsen via cfe-commits]

================
@@ -26,6 +30,13 @@ class CIRBaseBuilderTy : public mlir::OpBuilder {
   cir::PointerType getVoidPtrTy() {
     return getPointerTo(cir::VoidType::get(getContext()));
   }
+
+  mlir::TypedAttr getConstPtrAttr(mlir::Type t, int64_t v) {
----------------
dkolsen-pgi wrote:

Done.

I am still calibrating when to use the same names that are in the ClangIR incubator and when to choose better names.

https://github.com/llvm/llvm-project/pull/121069