Add blobtools as package for tf101
Created by: rrooij
This is for making a kernel image for the TF101 easier. See the pull request comment by Ollieparanoid for more information:
https://github.com/postmarketOS/pmbootstrap/pull/1103#issuecomment-357035481
The TF101 does not support normal Android boot images and instead needs a blob to be created.
This is my first package outside the device directory, so I hope I did it somewhat good. I can confirm that it builds successfully.