WIP: improve changed aport check error

The current error message displayed when the pkgver/pkgrel values don't exceed the current built package versions, or the pkgrel is not 0 for a new device is extremely verbose and can be confusing.

This MR updates the script to display a message based on which error occurred rather than using a catch-all.

v1 keeps the current print error and exit function but allows for 2 different errors to be printed, this comes with the side effect of only printing an error about incorrect pkgver for updated packages even if both errors occur.

v2 prints errors as they arise rather than at the end of the script, this makes it much more clear which package caused what error, however I'm sure there's room for improvement.