compiler: Fixup Bundle.nbytes

Author: FabioLuporini

devito/types/array.py

@@ -503,6 +503,10 @@ def symbolic_shape(self):
             # shape, i.e. something along the lines of  `(x_size, y_size, z_size)`
             return self.c0.symbolic_shape
 
+    @property
+    def nbytes(self):
+        return self.size*self.dtype.itemsize
+
     @property
     def _mem_heap(self):
         return not any([self._mem_stack, self._mem_shared, self._mem_shared_remote])