Add `muldiv_c` and `muxadd` peepopts #1536

Job	Run time
pre_job	5s
WASI build	20m 2s
Build nix flake (ubuntu-latest)	14m 29s
Build nix flake (macos-latest)	13m 52s
Prepare Visual Studio build	35s
Visual Studio build	10m 39s
	59m 42s

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