fix: return when none options

pydep/tools/cmakebuilder.py

@@ -10,6 +10,8 @@ class CMakePackageBuilder(PackageBuilder):
         self.cmakelists: CMakeLists = None
 
     def set_options(self, options):
+        if options is None:
+            return self
         options_dict = asdict(options)
         l = []
         for k, v in options_dict.items():