Update holoviews/plotting/mpl/chart.py

Co-Authored-By: Philipp Rudiger <prudiger@anaconda.com>

holoviews/plotting/mpl/chart.py

@@ -1222,7 +1222,7 @@ def get_data(self, element, ranges, style):
             style['array'] = element.dimension_values(cdim)
             self._norm_kwargs(element, ranges, style, cdim)
 
-        if 'spike_length' in self.lookup_options(element, 'plot').options:
+        if 'spike_length' in opts:
             axis_dims =  (element.dimensions()[0], None)
         elif len(element.dimensions()) == 1:
             axis_dims =  (element.dimensions()[0], None)