Fix #22663: Normalize bool bitfield to 0 or 1 during logical not optimizations

[bscuron]

#22663

true = -1
false = 0

!true case:
-1 & 1 => 1
1 ^ 1 => 0

!false case:
0 & 1 => 0
0 ^ 1 => 1

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[dkorpel]

This looks like the wrong place to fix. TYbool is supposed to be a 1-bit integer. If accessing a bool bitfield somehow generates a value of 0b11111111 or -1 then the masking should happen before it gets into an expression. Otherwise we need to check the logic for all TYbool operations (not just 'logical not') to handle arbitrary bit patterns, which generates more bytes of code even in cases where it's not necessary.