Can we get real 18A peak or ideally 21A peak current?

* at the moment GDI4 behavior changes at 18A commanded peak current: we have linear change of behavior up to and including 17.9A and then it falls off the cliff at 18A peak commanded
* in reality that 17.9A is more like 15.5A measured see https://github.com/rusefi/rusefi-hardware/issues/256
* fancy flow benching is asking for 18A measured or ideally 21A measured.  