Coverity reported error fixes: (ARMmbed#1822)

CIDs fixed: 276776, 276777, and 276778

Author: deepakvenugopal

source/6LoWPAN/Thread/thread_commissioning_api.c

@@ -257,7 +257,7 @@ static int thread_commissioning_active_get_cb(int8_t service_id, uint8_t source_
 
     tr_debug("management get response from comm module");
     if (!this) {
-        goto notify_user;
+        return -2;
     }
 
     if ((len = thread_meshcop_tlv_find(response_ptr->payload_ptr, response_ptr->payload_len, MESHCOP_TLV_NETWORK_MESH_LOCAL_ULA, &ptr)) > 0) {
@@ -268,7 +268,6 @@ static int thread_commissioning_active_get_cb(int8_t service_id, uint8_t source_
         common_write_16_bit(0xfc00, this->leader_address + 14);
     }
 
-    notify_user:
     if (this->status_cb_ptr) {
         this->status_cb_ptr(this->interface_id, this->session_id, state);
     }
@@ -280,7 +279,7 @@ static int commissioning_leader_petition_recv_cb(int8_t service_id, uint8_t sour
     commissioner_t *this = commissioner_find_by_service(service_id);
     commissioning_state_e state = COMMISSIONING_STATE_REJECT;
     uint16_t session_id = 0;
-    uint8_t *ptr;
+    uint8_t *ptr = NULL;
     char *uri_ptr = THREAD_URI_ACTIVE_GET;
     (void) source_address;
     (void) source_port;

source/6LoWPAN/Thread/thread_management_api.c

@@ -285,7 +285,10 @@ int thread_management_register(int8_t interface_id)
     this->interface_id = interface_id;
     this->set_response_cb_ptr = NULL;
     this->get_response_cb_ptr = NULL;
-    thread_management_get_remote_addr(this);
+
+    if (thread_management_get_remote_addr(this)) {
+        return -1;
+    }
 
     ns_list_add_to_start(&instance_list, this);
     if(this->native_interface) {