mdnssd: drop spurious QtCore dependency

Change-Id: Ia63975ea9d310a1ef67a41e160a9cf7b3125a07a
Reviewed-by: Christian Kandeler <christian.kandeler@nokia.com>

src/tools/mdnssd/mdnssd.pro

 QT       -= gui
+QT       -= core
 TEST = 0
 include(../../../qtcreator.pri)
 CONFIG -= console testlib TEST

src/tools/mdnssd/mdnssd.qbs

@@ -9,7 +9,6 @@ QtcTool {
     cpp.includePaths: [ ".",  buildDirectory ]
 
     Depends { name: "cpp" }
-    Depends { name: "Qt"; submodules: ['network' ] }
 
     files: [
         "uds_daemon.c", "uds_daemon.h",