tests hardware: Add machine_Counter.py.

This adds hardware tests for machine.Counter.
It requires two jumper wires between two pairs of pins,
outputs, and inputs.
output1: Pin() -> input1: Pin()
output2: Pin() -> input2: Pin()
or
output1: PWM() -> input1: Pin()
output2: PWM() -> input2: Pin()

machine.Pin and machine.PWM generates pulses and controls
the direction of counting, and machine.Counter inputs both.
machine.Timer generates a period for counting pulses.

machine.Counter value and irq callback tests are performed.

Signed-off-by: IhorNehrutsa <[email protected]>

Author: IhorNehrutsa