Fix covery scan warnings for wqueue

[julianoes]

This was my take at the coverity scan warnings:

** CID 341063: Uninitialized members (UNINIT_CTOR)
/src/include/containers/BlockingQueue.hpp: 49 in BlockingQueue<const px4::wq_config_t *, (unsigned long)1>::BlockingQueue()()


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*** CID 341063: Uninitialized members (UNINIT_CTOR)
/src/include/containers/BlockingQueue.hpp: 49 in BlockingQueue<const px4::wq_config_t *, (unsigned long)1>::BlockingQueue()()
43 public:
44
45 BlockingQueue()
46 {
47 px4_sem_init(&_sem_head, 0, N);
48 px4_sem_init(&_sem_tail, 0, 0);
>>> CID 341063: Uninitialized members (UNINIT_CTOR)
>>> Non-static class member "_data" is not initialized in this constructor nor in any functions that it calls.
49 }
50
51 ~BlockingQueue()
52 {
53 px4_sem_destroy(&_sem_head);
54 px4_sem_destroy(&_sem_tail);

** CID 196765: Null pointer dereferences (REVERSE_INULL)
/src/platforms/common/px4_work_queue/test/wqueue_start.cpp: 67 in wqueue_test_main()


________________________________________________________________________________________________________
*** CID 196765: Null pointer dereferences (REVERSE_INULL)
/src/platforms/common/px4_work_queue/test/wqueue_start.cpp: 67 in wqueue_test_main()
61
62 daemon_task = px4_task_spawn_cmd("wqueue",
63 SCHED_DEFAULT,
64 SCHED_PRIORITY_MAX - 5,
65 2000,
66 PX4_MAIN,
>>> CID 196765: Null pointer dereferences (REVERSE_INULL)
>>> Null-checking "argv" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.
67 (argv) ? (char *const *)&argv[2] : (char *const *)nullptr);
68
69 return 0;
70 }
71
72 if (!strcmp(argv[1], "stop")) {

[dagar]

Thanks @julianoes