tbf_{ul,dl}_fsm: remove impossible dst state transitions

There's no code path triggering change to those states.

Change-Id: I05b3019e12ec37e11ac2561a94b2eacec8718755
diff --git a/src/tbf_dl_fsm.c b/src/tbf_dl_fsm.c
index 65070d3..55a0156 100644
--- a/src/tbf_dl_fsm.c
+++ b/src/tbf_dl_fsm.c
@@ -375,8 +375,7 @@
 			X(TBF_EV_ASSIGN_ADD_CCCH) |
 			X(TBF_EV_ASSIGN_ADD_PACCH),
 		.out_state_mask =
-			X(TBF_ST_ASSIGN) |
-			X(TBF_ST_RELEASING),
+			X(TBF_ST_ASSIGN),
 		.name = "NEW",
 		.action = st_new,
 	},
diff --git a/src/tbf_ul_fsm.c b/src/tbf_ul_fsm.c
index 11ed8ab..13dc9fb 100644
--- a/src/tbf_ul_fsm.c
+++ b/src/tbf_ul_fsm.c
@@ -312,8 +312,7 @@
 			X(TBF_EV_ASSIGN_ADD_PACCH),
 		.out_state_mask =
 			X(TBF_ST_ASSIGN) |
-			X(TBF_ST_FLOW) |
-			X(TBF_ST_RELEASING),
+			X(TBF_ST_FLOW),
 		.name = "NEW",
 		.action = st_new,
 	},
@@ -325,8 +324,7 @@
 			X(TBF_EV_MAX_N3105),
 		.out_state_mask =
 			X(TBF_ST_FLOW) |
-			X(TBF_ST_FINISHED) |
-			X(TBF_ST_RELEASING),
+			X(TBF_ST_FINISHED),
 		.name = "ASSIGN",
 		.action = st_assign,
 		.onenter = st_assign_on_enter,