message: Remove unused mPSKc.
diff: @@ -168,7 +168,6 @@ private:
  char mInterfaceDBusName[DBUS_MAXIMUM_NAME_LENGTH + 1];
  char mInterfaceDBusPath[DBUS_MAXIMUM_NAME_LENGTH + 1];
  - uint8_t mPSKc[kSizePSKc];
  uint8_t mEui64[kSizeEui64];
  char mInterfaceName[IFNAMSIZ];
  DBusConnection *mDBus;
  