Feat h7 current sensing

[askuric]

• This PR adds the low-side current sensing for H7 boards.
• There are some cleanups of the driver code as well, minimal though
• The current sensing does not work with portenta for the moment - did not have on me at the moment so I could not really test the MBED integration properly.
• Also I've added portenta and a few other MBED boards to the compile CI

[askuric]

H7 low-side is working, I've tested it with the SimpleFOCMini v2.
Before this commit it did not work properly actually. It did not handle the repetition counter missing.

I did find something strange though. In the case where the repetition counter is handled in the software (in the interrupt handler) where we count and use every second measurement, for H7 we have to start from the 2nd call of the interrupt while the other architectures were starting from the 1st call. There is a shift of one interrupt call. I am not sure where does it come from.
I'm wondering if this shift is persistent between the architectures (always the same for the same family) or is it different for different timers, or is there something else going on. In any case I did not see this before.

We need to investigate this!

Here is the code for h7:

Arduino-FOC/src/current_sense/hardware_specific/stm32/stm32h7/stm32h7_mcu.cpp

Lines 146 to 149 in 302719c

	if( needs_downsample[adc_index] && tim_downsample[adc_index]++ > 1) {
	tim_downsample[adc_index] = 1;
	return;
	}

And for g4:

Arduino-FOC/src/current_sense/hardware_specific/stm32/stm32g4/stm32g4_mcu.cpp

Lines 158 to 161 in 302719c

	if( needs_downsample[adc_index] && tim_downsample[adc_index]++ > 0) {
	tim_downsample[adc_index] = 0;
	return;
	}