dyn TS: add ts->dyn state

Add state fields osmo_bts_trx_ts->dyn.* to record dynamic timeslot state.
Initialize in gsm_bts_trx_alloc().

Change-Id: I0a4049df8500b4f7c864f1355c4e9238932d1b8f
diff --git a/openbsc/include/openbsc/gsm_data_shared.h b/openbsc/include/openbsc/gsm_data_shared.h
index f3a8c32..8743c80 100644
--- a/openbsc/include/openbsc/gsm_data_shared.h
+++ b/openbsc/include/openbsc/gsm_data_shared.h
@@ -348,6 +348,12 @@
 
 	enum gsm_phys_chan_config pchan;
 
+	struct {
+		enum gsm_phys_chan_config pchan_is;
+		enum gsm_phys_chan_config pchan_want;
+		struct msgb *pending_chan_activ;
+	} dyn;
+
 	unsigned int flags;
 	struct gsm_abis_mo mo;
 	struct tlv_parsed nm_attr;