NFC: Refactor MIRPrinter into state struct and functions

Moves `MIRPRinter` and `MIPrinter` fields into a new `MFPrintState`
struct. Turns methods into independent functions.

- This slightly simplifies the code.
- This allow to pass the state around to other printing functions in the
  future without the need to expose the state struct to public
  headers.

Author: MatzeB