remove useless else in coeff_exp

Co-authored-by: Martin Rubey <[email protected]>

Author: xcaruso

src/sage/rings/function_field/drinfeld_modules/charzero_drinfeld_module.py

@@ -356,9 +356,8 @@ def coeff_log(k):
         if prec is Infinity:
             L = LazyPowerSeriesRing(self._base, name)
             return L(coeff_log, valuation=1)
-        else:
-            L = PowerSeriesRing(self._base, name, default_prec=prec)
-            return L([0] + [coeff_log(i) for i in range(1, prec)], prec=prec)
+        L = PowerSeriesRing(self._base, name, default_prec=prec)
+        return L([0] + [coeff_log(i) for i in range(1, prec)], prec=prec)
 
     @cached_method
     def _compute_goss_polynomial(self, n, q, poly_ring, X):