rbutil: show progress bar during bootloader uninstall

Useful for targets that needs multi-stage uninstall. On current
targets (with Uninstall capability) the progress is updated to
100% when bootloader uninstall is successfully finished.

Change-Id: I61be1c4f5cfc2d2f35fa5005962be9703888447d

rbutil/rbutilqt/base/bootloaderinstallfile.cpp

@@ -129,6 +129,7 @@ bool BootloaderInstallFile::uninstall(void)
     }
     emit logItem(tr("Original bootloader restored successfully."), LOGOK);
     logInstall(LogRemove);
+    emit logProgress(1, 1);
     emit done(false);
 
     return true;