Properly reset tL2C_CCB::ecoc

Bug: 171657571
Tag: #refactor
Test: act.py -tc BleCocTest
Change-Id: I491a7cba9b28dcc4d02d7de4463a3512e8fce719

system/stack/l2cap/l2c_int.h

@@ -306,7 +306,7 @@ typedef struct t_l2c_ccb {
   uint16_t remote_credit_count;
 
   /* used to indicate that ECOC is used */
-  bool ecoc;
+  bool ecoc{false};
   bool reconfig_started;
 } tL2C_CCB;
 

system/stack/l2cap/l2c_utils.cc

@@ -1452,6 +1452,7 @@ tL2C_CCB* l2cu_allocate_ccb(tL2C_LCB* p_lcb, uint16_t cid) {
   p_ccb->rx_data_rate = L2CAP_CHNL_DATA_RATE_LOW;
 
   p_ccb->is_flushable = false;
+  p_ccb->ecoc = false;
 
   alarm_free(p_ccb->l2c_ccb_timer);
   p_ccb->l2c_ccb_timer = alarm_new("l2c.l2c_ccb_timer");