Merge branch 'ax25-project-links'

Peter Lafreniere says:

====================
ax25: Update link for linux-ax25.org

http://linux-ax25.org has been down for nearly a year. Its official
replacement is https://linux-ax25.in-berlin.de.

Update all references to the dead link to its replacement.

As the three touched files are in different areas of the tree, this is
being sent with one patch per file.
====================

Signed-off-by: David S. Miller <[email protected]>