sgsn: Fix numbering of QoS and add basic description for APN

QoS was supposed to be 13 as 12 has been used for the APN. Fix that
and document the APN.

Change-Id: Ib6113aa7c59841aada424e2cafd94ed88c7badc7
1 file changed
tree: 774d7539a577d650e87d0a638adfa727b3527eaf
  1. doc/