Remove unnecessary headers from all-clusters-app main.

These got added along with code in initial drafts of
project-chip#11058 but then
the code was removed without removing the now-unnecessary headers.

examples/all-clusters-app/linux/main.cpp

@@ -16,17 +16,12 @@
  *    limitations under the License.
  */
 
-#include <app-common/zap-generated/callback.h>
-#include <app-common/zap-generated/ids/Clusters.h>
 #include <app/Command.h>
-#include <app/ConcreteAttributePath.h>
 #include <app/clusters/identify-server/identify-server.h>
 #include <app/util/af.h>
 
 #include "AppMain.h"
 
-using namespace chip;
-
 bool emberAfBasicClusterMfgSpecificPingCallback(chip::app::Command * commandObj)
 {
     emberAfSendDefaultResponse(emberAfCurrentCommand(), EMBER_ZCL_STATUS_SUCCESS);