Create request channel reason to see channel requests originating from PAG

diff --git a/include/openbsc/gsm_04_08.h b/include/openbsc/gsm_04_08.h
index b9a2cc8..081e869 100644
--- a/include/openbsc/gsm_04_08.h
+++ b/include/openbsc/gsm_04_08.h
@@ -344,6 +344,7 @@
 void gsm0408_generate_lai(struct gsm48_loc_area_id *lai48, u_int16_t mcc, 
 		u_int16_t mnc, u_int16_t lac);
 enum gsm_chan_t get_ctype_by_chreq(struct gsm_bts *bts, u_int8_t ra);
+enum gsm_chreq_reason_t get_reason_by_chreq(struct gsm_bts *bts, u_int8_t ra);
 
 
 #endif