Added support for PocketBeagle2

[explodeo]

Add PocketBeagle 2 autodetection.
I'm not sure how to handle multi-line EEPROM IDs when the library only checks the first 16 bytes. Instead, I added lines 372-374 in board.py

# add support for PocketBeagle 2
# should be caught in the else clause at the bottom but I couldn't figure it out
if eeprom_bytes == b"\xaaU3\xee\x017\x00\x10.\x00POCKET":
    return boards.BEAGLEBONE_POCKETBEAGLE_2

Testing Results below:

(blinka-env) debian@sierra:~/Adafruit_Python_PlatformDetect/bin$ ./detect.py 
Board Detection Test

Check that the Chip and Board IDs match your board and that this it is
correctly detecting whether or not it is a Linux board.

Chip id:  AM625X
Board id:  BEAGLEBONE_POCKETBEAGLE_2

Linux Detection
---------------
Is this an embedded Linux system? True

Raspberry Pi Boards
-------------------
Is this a Pi 3B+? False
Is this a Pi 4B? False
Is this a 40-pin Raspberry Pi? False
Is this a Raspberry Pi Compute Module? False

Other Boards
-------------------
Is this a Siemens Simatic IOT2000 Gateway? False
Is this a 96boards board? False
Is this a BeagleBone board? True
Is this a Giant board? False
Is this a Coral Dev board? False
Is this a MaaXBoard? False
Is this a SiFive board?  False
Is this a PYNQ board? False
Is this a Rock Pi board? False
Is this a NanoPi board? False
Is this a Khadas VIM3 board? False
Is this a Clockwork Pi board? False
Is this a Seeed Board? False
Is this a UDOO board? False
Is this an ASUS Tinker board? False
Is this an STM32MP1 board? False
Is this a MilkV board? False
Is this a Luckfox Pico board? False
Is this a generic Linux PC? False
Is this an OS environment variable special case? False