libbsc: add chreq type for CHREQ_T_PDCH_ONE_PHASE & CHREQ_T_PDCH_TWO_PHASE

When using a BSC located PCU the BSC must understand PDCH requests.

Change-Id: Ie7f4ed000cf1b40d269873cf0ddf5ff9f5bbc18a
diff --git a/openbsc/include/openbsc/gsm_data_shared.h b/openbsc/include/openbsc/gsm_data_shared.h
index 7c469ee..e697cb8 100644
--- a/openbsc/include/openbsc/gsm_data_shared.h
+++ b/openbsc/include/openbsc/gsm_data_shared.h
@@ -46,6 +46,7 @@
 	GSM_CHREQ_REASON_CALL,
 	GSM_CHREQ_REASON_LOCATION_UPD,
 	GSM_CHREQ_REASON_OTHER,
+	GSM_CHREQ_REASON_PDCH,
 };
 
 /* lchans 0..3 are SDCCH in combined channel configuration,