In Release 5, Fixed Allocations were removed as part of a "GPRS
simplification project" inside 3PGPP. This means that any MS compatible
with Rel-5 or higher may not support it, which makes implementation
in the PCU af historical interest only. See Tdoc GP-021277 for the
actual removal, it happened at 5.0.0 time.
Change-Id: I8138bc0a47d3468b67cec866447fd4b0fc69d4c5