coerce fixedrange in 'missing' axis loop

- this does not fix any bugs as the downstream fixedrange check use
  !fixedrange, but it's probably a good idea to get this into
  fullLayout to avoid potential bugs down the road.

Author: etpinard

src/plots/cartesian/layout_defaults.js

@@ -315,6 +315,8 @@ module.exports = function supplyLayoutDefaults(layoutIn, layoutOut, fullData) {
             grid: layoutOut.grid
         });
 
+        coerce('fixedrange');
+
         addMissingMatchedAxis(axLayoutIn.matches);
 
         axLayoutOut._input = axLayoutIn;