[core] Coverity fixes

* [core] Coverity 1518099, 1518097, 1518098 (Unchecked return value from library)

* [core] Coverity 1468551 Unchecked return value

* [core] Coverity 1468293 Unchecked return value

* [core] Coverity 1468274 Explicit null dereferenced

* [core] Coverity 1395588 Unchecked return value

* [core] Coverity 1395515 Logically dead code

* [core] Coverity 1364984 Result is not floating-point

* [core] Coverity 1395554, 1468440 Dereference before null check

* [core] Coverity 1024487 Dereference after null check

* [core] Coverity 1024872 Unchecked return value

* [core] Coverity 1025822 Unchecked return value

* [core] Coverity 1025823 Unchecked return value

* [core] Coverity 1087637, 1346467, 1087638 Unchecked return value

* [core] Coverity 1107607 Unchecked return value

* [core] Coverity 1210777 Unchecked return value

* [core] Coverity 1227670 Dereference before null check

* [core] Coverity 1024551 Logically dead code

* [core] Coverity 1024560 Logically dead code

* [core] Coverity 1024664 Operands don't affect result

* [core] Coverity 1364957 Dereference after null check

* [core] Coverity 1395572 Logically dead code

* [core] Coverity 1412459 Unchecked return value

* [core] Coverity 1412490 Unchecked return value

* [core] Coverity 1395515/2 Logically dead code

* [core] Coverity cleanup

src/switch_core_sqldb.c

@@ -2065,6 +2065,7 @@ static uint32_t do_trans(switch_sql_queue_manager_t *qm)
 	switch_status_t status;
 	uint32_t ttl = 0;
 	uint32_t i;
+	switch_status_t res;
 
 	if (!zstr(qm->pre_trans_execute)) {
 		switch_cache_db_execute_sql_real(qm->event_db, qm->pre_trans_execute, &errmsg);
@@ -2126,7 +2127,8 @@ static uint32_t do_trans(switch_sql_queue_manager_t *qm)
 
 		for (i = 0; (qm->max_trans == 0 || ttl <= qm->max_trans) && (i < qm->numq); i++) {
 			switch_mutex_lock(qm->mutex);
-			switch_queue_trypop(qm->sql_queue[i], &pop);
+			res = switch_queue_trypop(qm->sql_queue[i], &pop);
+			(void)res;
 			switch_mutex_unlock(qm->mutex);
 			if (pop) break;
 		}
@@ -2138,6 +2140,7 @@ static uint32_t do_trans(switch_sql_queue_manager_t *qm)
 				switch_mutex_unlock(qm->mutex);
 				ttl++;
 			}
+
 			switch_safe_free(pop);
 			if (status != SWITCH_STATUS_SUCCESS) break;
 		} else {
@@ -2153,7 +2156,6 @@ static uint32_t do_trans(switch_sql_queue_manager_t *qm)
 		}
 	}
 
-
  end:
 
 	switch(qm->event_db->type) {
@@ -2190,11 +2192,11 @@ static uint32_t do_trans(switch_sql_queue_manager_t *qm)
 		}
 	}
 
-
 	switch_mutex_lock(qm->mutex);
 	for (i = 0; i < qm->numq; i++) {
 		qm->written[i] = qm->pre_written[i];
 	}
+
 	switch_mutex_unlock(qm->mutex);
 
 	return ttl;