Remove attribute `def_orient` of `SHPC_class`

We do not need it. we can just have a local variable at initialization.

Common/util_eddies.py

@@ -25,7 +25,6 @@ class SHPC_class:
             raise OSError
 
         self.dir = SHPC_dir
-        self.def_orient = def_orient
 
         # <begin> Define self.n_slices
 
@@ -106,7 +105,7 @@ class SHPC_class:
 
         # We only need ishape_last for the last slice, for one
         # orientation, in order to define n_dates:
-        ishape_last = self.get_ishape_last(self.n_slices - 1, self.def_orient)
+        ishape_last = self.get_ishape_last(self.n_slices - 1, def_orient)
 
         self.n_dates = np.ediff1d(self.d_init, to_end=ishape_last.size)
         self._i_slice = []