Add `muldiv_c` and `muxadd` peepopts #1536

Job	Run time
pre_docs_job	4s
pre_job	6s
Try build docs (html)	1m 5s
Reusable build (ubuntu-latest)	15m 47s
Try build docs (latexpdf)	1m 0s
Reusable build (macos-latest)	7m 22s
Run tests (ubuntu-latest)	6m 39s
Run docs tests (ubuntu-latest)	30s
Run tests (macos-latest)	7m 36s
	40m 9s

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