Doc: Tweak function prototype indentation for consistency.

Author: Etsuro Fujita

doc/src/sgml/fdwhandler.sgml

@@ -622,10 +622,10 @@ ExecForeignInsert(EState *estate,
 <programlisting>
 TupleTableSlot **
 ExecForeignBatchInsert(EState *estate,
-                  ResultRelInfo *rinfo,
-                  TupleTableSlot **slots,
-                  TupleTableSlot **planSlots,
-                  int *numSlots);
+                       ResultRelInfo *rinfo,
+                       TupleTableSlot **slots,
+                       TupleTableSlot **planSlots,
+                       int *numSlots);
 </programlisting>
 
      Insert multiple tuples in bulk into the foreign table.