Fix keeping of package info during repository update.

* actually write the package info read from the repository, not the one
  from the package, as the latter is missing the checksum

src/bin/package_repo/command_update.cpp

@@ -324,7 +324,8 @@ command_update(int argc, const char* const* argv)
 		PackageInfos::iterator infoIter = packageInfos.find(packageInfo);
 		if (infoIter != packageInfos.end()) {
 			infoIter->second = true;
-			if ((result = repositoryWriter.AddPackageInfo(packageInfo)) != B_OK)
+			if ((result = repositoryWriter.AddPackageInfo(infoIter->first))
+					!= B_OK)
 				return 1;
 			if (verbose) {
 				printf("keeping '%s-%s'\n", infoIter->first.Name().String(),