Cleanup patch from Denis Vlasenko.  Mostly variants of removing the if(x)
from before "if(x) free(x)".
diff --git a/archival/dpkg.c b/archival/dpkg.c
index 70eaefb..74d3a83 100644
--- a/archival/dpkg.c
+++ b/archival/dpkg.c
@@ -544,8 +544,7 @@
 		for (i = 0; i < node->num_of_edges; i++) {
 			free(node->edge[i]);
 		}
-		if ( node->edge )
-			free(node->edge);
+		free(node->edge);
 		free(node);
 	}
 }