use StartDpkg() in PackageManagerProgressDeb822Fd as well

apt-pkg/install-progress.cc

@@ -149,7 +149,7 @@ void PackageManagerProgressDeb822Fd::WriteToStatusFd(std::string s)
    FileFd::Write(OutStatusFd, s.c_str(), s.size());   
 }
 
-void PackageManagerProgressDeb822Fd::Start()
+void PackageManagerProgressDeb822Fd::StartDpkg()
 {
    // FIXME: use SetCloseExec here once it taught about throwing
    //        exceptions instead of doing _exit(100) on failure

apt-pkg/install-progress.h

@@ -97,7 +97,7 @@ namespace Progress {
  public:
     PackageManagerProgressDeb822Fd(int progress_fd);
 
-    virtual void Start();
+    virtual void StartDpkg();
     virtual void Stop();
 
     virtual bool StatusChanged(std::string PackageName,