Fix steplist bug in check_manifest()
Steplist defvalue is [], so we shouldn't compare to None to check if
it's unset.
@@ -1582,7 +1582,7 @@ class Chip:
'''
steplist = self.get('steplist')
- if steplist is None:
+ if not steplist:
steplist = self.list_steps()
#1. Checking that flowgraph is legal
