Interrupt: Stop relying on parity of the status register.
At some point in the past it helped the split to be handled in time in the
presence of profiling debug markers, however since aba30d6a9aeb we no longer do
this through a Z80 instruction but hook it up entirely through emulator
breakpoints, so we don’t need to be so extremely optimal here anymore.
Moreover, this makes it more robust in the face of someone making let’s say a
new FPGA VDP with a new VDP ID. The alternative would’ve been to determine
whether to check for pe or po at runtime, but it’s easier to just get rid of it.
Additionally fix Interrupt_Return indentation.