fix: mcu slave tbs, wait for sync rst

feat: synchronize reset in mcu slave tops

tests: add regs mcu_slave test

refactor: get rid of sda, scl overrides, drive sda, scl directly

refactor: use 'H' std_logic state instead of custom pull up type

tests: add possibility to check sda stability in mcu_slave

tests: add mcu_slave counter tb