... and update our copyright.py script to set environment variable
UPDATE_COPYRIGHT_USE_INTERVALS to '2' instead of '1'. This tells
the script to collapse all years into one single interval.
gdb/ChangeLog:
* gnulib/extra/update-copyright: Update to the latest from
gnulib's git repository.
* copyright.py: Set UPDATE_COPYRIGHT_USE_INTERVALS environment
variable to 2 instead of 1.