Naming convention: Uppercase device codename

Either the wiki doesn't have that infromation: https://github.com/postmarketOS/pmbootstrap/wiki/Package-naming-convention Or the pmbootstrap tool doesn't like uppercase package names.

Example:

luca@g550jk /m/h/p/pmbootstrap> ./pmbootstrap.py checksum device-fairphone-FP2
CRITICAL:root:You will need to create a device-specific package
CRITICAL:root:before you can continue. Please create at least the
CRITICAL:root:following files:
CRITICAL:root:/mnt/hdd/postmarketOS/pmbootstrap/aports/device-fairphone-fp2/APKBUILD
CRITICAL:root:/mnt/hdd/postmarketOS/pmbootstrap/aports/device-fairphone-fp2/deviceinfo
Traceback (most recent call last):
  File "./pmbootstrap.py", line 69, in <module>
    sys.exit(main())
  File "./pmbootstrap.py", line 35, in main
    args = pmb.parse.arguments()
  File "/mnt/hdd/postmarketOS/pmbootstrap/pmb/parse/arguments.py", line 236, in arguments
    setattr(args, "deviceinfo", pmb.parse.deviceinfo(args))
  File "/mnt/hdd/postmarketOS/pmbootstrap/pmb/parse/deviceinfo.py", line 38, in deviceinfo
    raise RuntimeError("Incomplete device information")
RuntimeError: Incomplete device information