ppp: Bug#13164 - Update configure options to have correct directory for pid

ppp: Bug#13164 - Update configure options to have correct directory for pid

- The original poster of the bug#13164 has already tested out ppp-2.5.0 in CU179 (master)
   and identified that the startup could not find the directory /usr/var/run/. This is due
   to the change in use of the prefix command in 2.5.0 vs 2.4.9 so --localstatedir set to
   /var. runstatedir is then set to localstatedir/run ie /var/run which is then correct
   for IPFire.
- This fix needs to be implemented into CU179 so that the bug poster can test out the update
- Updated rootfile to remove additional empty line

Fixes: Bug#13164
Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>