DNS: Fix return value for successful name resolutions

Author: bulislaw

features/netsocket/nsapi_dns.cpp

@@ -217,7 +217,7 @@ static int nsapi_dns_query_multiple(NetworkStack *stack, const char *host,
         return NSAPI_ERROR_NO_MEMORY;
     }
 
-    int result = NSAPI_ERROR_DNS_FAILURE;
+    int result = NSAPI_ERROR_OK;
 
     // check against each dns server
     for (unsigned i = 0; i < DNS_SERVERS_SIZE; i++) {
@@ -243,8 +243,11 @@ static int nsapi_dns_query_multiple(NetworkStack *stack, const char *host,
         }
 
         const uint8_t *response = packet;
-        dns_scan_response(&response, addr, addr_count);
-        break;
+        if (!dns_scan_response(&response, addr, addr_count)) {
+            result = NSAPI_ERROR_DNS_FAILURE;
+        } else {
+            break;
+        }
     }
 
     // clean up packet