gsm0408: add chreq_type for CHREQ_T_PDCH_ONE_PHASE and CHREQ_T_PDCH_TWO_PHASE

The previous version of this commit got reverted to avoid a breakage in openbsc.
The problem is openbsc use an array of chreq_type with a manual defined size. This array
is using enums as index which breaks if any elements got added into the
middle, because the size of the array can't hold elements greater or
equal than the size.

Change-Id: I6676105507fe4e5627f740dfe4c2770f766ad068
1 file changed