[clang] [CIR] Layout _BitInt types in record/array in CIR as it is in LLVM-IR (PR #219487)

[Erich Keane via cfe-commits]

================
@@ -76,4 +76,8 @@ mlir::Value createAnd(mlir::OpBuilder &bld, mlir::Value lhs,
                       const llvm::APInt &rhs);
 
 mlir::Value createLShR(mlir::OpBuilder &bld, mlir::Value lhs, unsigned rhs);
+
+mlir::Type convertTypeForMemory(const mlir::TypeConverter &converter,
----------------
erichkeane wrote:

This was just moved/copy-pasted out of LowerToLLVM so that we can use it in LoweringHelpers.

https://github.com/llvm/llvm-project/pull/219487