Get rid of lambda within HIR::MethodCallExpr

[philberty]

gccrs/gcc/rust/hir/tree/rust-hir-expr.h

Lines 1742 to 1749 in 99c2830

	void iterate_params (std::function<bool (Expr *)> cb)
	{
	for (auto &param : params)
	{
	if (!cb (param.get ()))
	return;
	}
	}

Lambda's like this need to be removed they make working with the IR's more complex for static analysis. To fix this issue you should be able to remove this lambda helper function and provide a method to return a reference to the values like

Create a new helper to access the elements:

std::vector<Expr>& get_arguments() { return params; }

Note this class also refers to the arguments in a Call as parameters which is confusing.