edge: Add work-around to get DL EGPRS from MS object

The EGPRS multi-slot class need to be parsed from the CSN.1 RA
capability (see gprs_bssgp_pcu_rx_dl_ud).

This commit adds a workaround to get the EGPRS MS class from the MS
object if that is present.

Sponsored-by: On-Waves ehf
1 file changed