Allow const patterns of matches to contain pattern types Trying to pattern match on a type containing a pattern type will currently fail with an ICE ```rust error: internal compiler error: compiler/rustc_mir_build/src/builder/matches/test.rs:459:18: invalid type for non-scalar compare: (u32) is 1.. --> src/main.rs:22:5 | 22 | TWO => {} | ^^^ ``` because the compiler tries to generate a MIR `BinOp(Eq)` operation on a pattern type, which is not supported. While we could support that, there are side effects of allowing this (none that would compile, but the compiler would simultaneously think it could `==` pattern types and that it could not because `PartialEq` is not implemented. So instead I change the logic for pattern matching to transmute pattern types to their base type before comparing. r? ```@BoxyUwU``` cc #123646 ```@scottmcm``` ```@joshtriplett```