Make TBF state private

Let's make sure no external function can mess with the TBF state.

Change-Id: I217f4c4bac21dd584c8682928a080a1a6e9507e1
diff --git a/src/tbf.cpp b/src/tbf.cpp
index 9c1dac9..9e3a8ef 100644
--- a/src/tbf.cpp
+++ b/src/tbf.cpp
@@ -174,7 +174,6 @@
 	n3105(0),
 	fT(0),
 	num_fT_exp(0),
-	state(GPRS_RLCMAC_NULL),
 	was_releasing(0),
 	upgrade_to_multislot(0),
 	bts(bts_),
@@ -185,6 +184,7 @@
 	m_ms(NULL),
 	m_ta(GSM48_TA_INVALID),
 	m_ms_class(0),
+	state(GPRS_RLCMAC_NULL),
 	m_list(this),
 	m_ms_list(this),
 	m_egprs_enabled(false)
diff --git a/src/tbf.h b/src/tbf.h
index 9491f2a..943ec92 100644
--- a/src/tbf.h
+++ b/src/tbf.h
@@ -284,10 +284,6 @@
 		Meas();
 	} meas;
 
-	/* these should become protected but only after gprs_rlcmac_data.c
-	 * stops to iterate over all tbf in its current form */
-	enum gprs_rlcmac_tbf_state state;
-
 	/* Remember if the tbf was in wait_release state when we want to
 	 * schedule a new dl assignment */
 	uint8_t was_releasing;
@@ -327,6 +323,7 @@
 	uint8_t m_ms_class;
 
 private:
+	enum gprs_rlcmac_tbf_state state;
 	LListHead<gprs_rlcmac_tbf> m_list;
 	LListHead<gprs_rlcmac_tbf> m_ms_list;
 	bool m_egprs_enabled;