By passing through the I2C instance to the application callbacks, the
application can implement multiple I2C slave devices on different
peripherals (eg I2C1 and I2C2).
This commit also adds a proper rw argument to i2c_slave_process_addr_match
for F7/H7/WB MCUs, and enables the i2c_slave_process_tx_end callback.
Mboot is also updated for these changes.
Signed-off-by: Damien George <damien@micropython.org>