aco/ra: Avoid redundant RegisterFile copies in get_reg_impl
(This is a followup to !7461 (merged).)
Now that this function does not block RegisterFile entries anymore, the temporary copy is only needed upon reaching the collect_vars call.
(This is a followup to !7461 (merged).)
Now that this function does not block RegisterFile entries anymore, the temporary copy is only needed upon reaching the collect_vars call.