Comment 6 for bug 1578745

Debdiff updated with postinst config test for config.txt ^device_tree_address=. If not found, it adds:

# Added by linux-firmware-raspi2
device_tree_address=0x100
device_tree_end=0x8000

Tested with vanilla raspi2 install + upgrade to 1.20160503+6832d9a-0ubuntu1, and subsequent reinstalls.