Add new BTS level counters

Adds counters for Immediate Assignment Reject, Packet Access Reject,
Channel Request Description and Final Block resend.

Change-Id: I23e326d4ea489aa4967e452fe02773b44ab146f7
diff --git a/src/tbf_dl.cpp b/src/tbf_dl.cpp
index 185521d..c6f3945 100644
--- a/src/tbf_dl.cpp
+++ b/src/tbf_dl.cpp
@@ -454,6 +454,7 @@
 		LOGP(DRLCMACDL, LOGL_DEBUG,
 			"- Nothing else to send, Re-transmit final block!\n");
 		bsn = m_window.v_s_mod(-1);
+		bts->rlc_final_block_resent();
 		bts->rlc_resent();
 	}