Missed optimization multiplication by const for cakeml

This issue is about optimizing the multiplication const in wordLang.
Note that pancake does this for known power of 2 [1] but it can be done smarter. see example llvm[2].

[1] https://github.com/CakeML/cakeml/blob/f37b65230f6b4665a5ac7b1730ef01bcf24115de/pancake/crep_arithScript.sml#L52C1-L59C4

[2] https://godbolt.org/#z:OYLghAFBqd5QCxAYwPYBMCmBRdBLAF1QCcAaPECAMzwBtMA7AQwFtMQByARg9KtQYEAysib0QXACx8BBAKoBnTAAUAHpwAMvAFYTStJg1DIApACYAQuYukl9ZATwDKjdAGFUtAK4sGIM6SuADJ4DJgAcj4ARpjE/hqkAA6oCoRODB7evv5JKWkCIWGRLDFxZgl2mA7pQgRMxASZPn4BldUCtfUEhRHRsfG2dQ1N2a1D3aG9Jf3lAJS2qF7EyOwcAPRrANQAKgCeiZibu4vEm2hYmwixmKSbJJu0qEzom4abmKqsifQAdCYaAEFQgRNo42AoAMwQYGbBg%2BWabEwAdisgM26M2xEwBCWDFhPk2ACpNhCTBDUQDkQARf6UwG0mFgzAKSTQwT4lgI5EUjGY7G4jlEzaSMkU6m0hnspkKACsbJBcM5iJRtN5WJxxDxiqFMtFEqRNPpgMZeHBADZ5RyuSq0Rj1QLtcSzXr6QbJSDpVwzJbFdaeXb%2BZrBcSvS7KW7jVLTcyuFCYb7lf70fag47NrGw9SOPNaJwZbw/BwtKRUJw3NZrJsFCcVoizBCeKQCJps/MANYgCEQn5d3t9/tm/ScSQFlslzi8BQgBLNovZ0hwWBINAsRJ0WLkSgrtf0OL1FgANwAHABaZAGIwngjELwMNt8OgEWJTiBRMdRUL1XacRsf5jEXYAHkom0KpZ0bFc2EEQCGFob851ILAoi8YA3DEWgp24XgsBYQxgHEBD8CxaoD2ZMcPiqLwnx/XhgUwXMENoPAomIL8PCwMdr1NGjSFI4gohSTAqUwXCjCYowW3mKgDGABQADU8EwAB3QCDkLYt%2BEEEQxHYKQZEERQVHUBDdC4fQ8JQCtLH0Zip0geZUESRwBEwk9AIhXhUD44g8CwOyIHmNpnL8CBXBGPwzOCSZilKPRklSYLwrivJgp6GL%2BjMoKanGJLMvosDsq6NK%2BjiTKcs8Zo9AUcZiumUrAprXSczzUcENLDhXmIQ9TyYM4L2ATYIGvW82wRCBcEIe5zAbWZeFnLRZnbTtu37Vbe0HBiR1IdTPInWxpybSSFxgRAQGkphZM3CBt3XYgADEZNc9zeBu3dwlYVZVCPM0TzNSQ%2BrwwbhrvWbAnwIgfPQPRNOEURxD0mHDLUMdTKbLFMF86dmo4fNtrHdrhLqdcXg8Vdbs2B6LoUTrupPXrz0BoabxBwaJohusG1uUmd1iDmuFB%2BbW1IDsux7NbVqHDgtp28cOEnA7BcWyWzFa4t2rmyT5j41JnEkIA%3D%3D%3D