Distinguish between unsupported and invalid MCS

Previously MCS0 was incorrectly set for some of type1 header values
while according to 3GPP TS 44.060 it can only be set for type3. Fix
this:

* use EGPRS_MCS* constants instead of magic values
* do not set MCS0 for reserved bits values in EGPRS header type1
* return different error codes for invalid and unsupported MCS as well
  as for other decoding errors

Note: there's no need to adjust tests because MCS0 decoding is not
supported but it's better to explicitly distinguish between unsupported
and invalid values nevertheless.

Change-Id: Id665d5c0cf50efa18b1bcbf4f17359418a380f9e
Related: OS#1524

0 files changed, 0 insertions, 0 deletions