[topgen] Clean up some flake8 warnings

Signed-off-by: Philipp Wagner <phw@lowrisc.org>
diff --git a/util/topgen/intermodule.py b/util/topgen/intermodule.py
index 2cc3d49..e8c6cba 100644
--- a/util/topgen/intermodule.py
+++ b/util/topgen/intermodule.py
@@ -911,7 +911,6 @@
     err, obj = check_intermodule_field(sig)
     assert not err
 
-
     # Floating signals
     # TODO: Find smarter way to assign default?
     if "top_signame" not in obj or default_name:
diff --git a/util/topgen/resets.py b/util/topgen/resets.py
index d75b18f..264de81 100644
--- a/util/topgen/resets.py
+++ b/util/topgen/resets.py
@@ -120,7 +120,6 @@
                 for reset in self.nodes.values()
                 if reset.gen]
 
-
     def get_top_resets(self) -> list:
         '''Get resets pushed to the top level'''
 
@@ -145,7 +144,6 @@
         if reset.rst_type == 'ext':
             return reset.path
 
-
         if shadow:
             path = reset.shadow_path
         else:
@@ -156,7 +154,6 @@
 
         return path
 
-
     def get_unused_resets(self, domains: list) -> Dict[str, str]:
         '''Get unused resets'''