Add support for flashing vbmeta destination in aboot-deploy script

This adds support for flashing a vbmeta partition in the aboot-deploy script. The new option -v or --vbmeta-destination allows users to explicitly specify the destination for the vbmeta partition. If this option is not provided, the script will determine the appropriate vbmeta destination based on the new slot and configuration.

The script also checks for the existence of the vbmeta destination and that the partition is large enough before proceeding with the deployment.

The script now deploys both the Android Boot Image and the vbmeta image to their respective destinations using dd.

Signed-off-by: Eric Curtin ecurtin@redhat.com