Rollup merge of #142528 - fee1-dead-contrib:push-rlxklunqkwmv, r=RalfJung

clarify `rustc_do_not_const_check` comment

~~Given that we have used this attribute for other reasons before it seems appropriate to make this a "usually".~~

Add function name as a pointer

cc ```@rust-lang/wg-const-eval```

Author: Kobzol