Replace PollController with newly added PDCH UL Controller

TbfTest is updated to submit empty blocks to have somehow meaningful
output (at least as meaningful test results as before, not much). That's
because we must update bts->curr_fn to have polls expire.

Related: OS#5020
Change-Id: I683ca738ce5a133c49c36a1d94439a942d64a831
diff --git a/src/tbf.h b/src/tbf.h
index 989ec08..779bc26 100644
--- a/src/tbf.h
+++ b/src/tbf.h
@@ -209,6 +209,7 @@
 int tbf_assign_control_ts(struct gprs_rlcmac_tbf *tbf);
 int tbf_check_polling(const struct gprs_rlcmac_tbf *tbf, uint32_t fn, uint8_t ts, uint32_t *poll_fn, unsigned int *rrbp);
 void tbf_set_polling(struct gprs_rlcmac_tbf *tbf, uint32_t new_poll_fn, uint8_t ts, enum gprs_rlcmac_tbf_poll_type t);
+void tbf_poll_timeout(struct gprs_rlcmac_tbf *tbf);
 #ifdef __cplusplus
 }
 #endif