Update the function immediate assignment for EGPRS

Encode the EGPRS fields of immediate assignment message in uplink
when EGPRS PACKET CHANNEL REQUEST (11 bit RACH) is received.
The series of patches for 11 bit RACH are dependent on libosmocore
and osmo-bts patches for 11 bit RACH.

Change-Id: Ie5e309156e5dbbb6add74a1b4d257c4ee2332e52
diff --git a/src/encoding.h b/src/encoding.h
index 710de78..69f8cdc 100644
--- a/src/encoding.h
+++ b/src/encoding.h
@@ -23,6 +23,9 @@
 #include <stdint.h>
 #include <gsm_rlcmac.h>
 #include <gprs_coding_scheme.h>
+extern "C" {
+#include <osmocom/gsm/l1sap.h>
+}
 
 struct gprs_rlcmac_bts;
 struct gprs_rlcmac_tbf;
@@ -40,11 +43,14 @@
 public:
 	static int write_immediate_assignment(
 			struct gprs_rlcmac_tbf *tbf,
-			bitvec * dest, uint8_t downlink, uint8_t ra,
+			bitvec * dest, uint8_t downlink, uint16_t ra,
 			uint32_t ref_fn, uint8_t ta, uint16_t arfcn, uint8_t ts,
 			uint8_t tsc, uint8_t usf, uint8_t polling,
 			uint32_t fn, uint8_t alpha, uint8_t gamma,
-			int8_t ta_idx);
+			int8_t ta_idx,
+			enum ph_burst_type burst_type =
+				GSM_L1_BURST_TYPE_ACCESS_0,
+			uint8_t sb = 1);
 
 	static void write_packet_uplink_assignment(
 			struct gprs_rlcmac_bts *bts,