Hot Plugging Support

• Add register_hotplug_callback() support
• portentaMachineControlPowerHandling() can discriminate between Portenta H7 and Portenta Machine Control targets
• Arduino_POSIXStorage_Test.ino now selects the Portenta C33 SD card TEST_PORTENTA_H7_SDCARD as the default TestType

What's Changed

• Add extended callback support by @alrvid in #12

Full Changelog: v1.1.1...1.1.2