stm32/network_wiznet5k: Fix build error with wiznet5k and lwip enabled.

Commit 4dba04a50f refactored the network code
but the combination of MICROPY_PY_WIZNET5K=5500 and MICROPY_PY_LWIP=1
broke.

ports/stm32/mpconfigport.h

@@ -253,7 +253,11 @@ extern const struct _mp_obj_type_t mp_network_cyw43_type;
 #endif
 
 #if MICROPY_PY_WIZNET5K
+#if MICROPY_PY_LWIP
+extern const struct _mp_obj_type_t mod_network_nic_type_wiznet5k;
+#else
 extern const struct _mod_network_nic_type_t mod_network_nic_type_wiznet5k;
+#endif
 #define MICROPY_HW_NIC_WIZNET5K             { MP_ROM_QSTR(MP_QSTR_WIZNET5K), MP_ROM_PTR(&mod_network_nic_type_wiznet5k) },
 #else
 #define MICROPY_HW_NIC_WIZNET5K

ports/stm32/mpnetworkport.c

@@ -48,6 +48,10 @@
 // Poll lwIP every 128ms
 #define LWIP_TICK(tick) (((tick) & ~(SYSTICK_DISPATCH_NUM_SLOTS - 1) & 0x7f) == 0)
 
+#if MICROPY_PY_WIZNET5K
+void wiznet5k_poll(void);
+#endif
+
 u32_t sys_now(void) {
     return mp_hal_ticks_ms();
 }

ports/stm32/network_wiznet5k.c

@@ -269,7 +269,7 @@ STATIC mp_obj_t wiznet5k_make_new(const mp_obj_type_t *type, size_t n_args, size
     mp_hal_pin_obj_t rst = pin_find(args[2]);
 
     // Access the existing object, if it has been constructed with the same hardware interface
-    if (wiznet5k_obj.base.type == &mod_network_nic_type_wiznet5k) {
+    if (wiznet5k_obj.base.type == (mp_obj_type_t *)&mod_network_nic_type_wiznet5k) {
         if (!(wiznet5k_obj.spi == spi && wiznet5k_obj.cs == cs && wiznet5k_obj.rst == rst
               && wiznet5k_obj.netif.flags != 0)) {
             wiznet5k_deinit();
@@ -277,7 +277,7 @@ STATIC mp_obj_t wiznet5k_make_new(const mp_obj_type_t *type, size_t n_args, size
     }
 
     // Init the wiznet5k object
-    wiznet5k_obj.base.type = &mod_network_nic_type_wiznet5k;
+    wiznet5k_obj.base.type = (mp_obj_type_t *)&mod_network_nic_type_wiznet5k;
     wiznet5k_obj.cris_state = 0;
     wiznet5k_obj.spi = spi;
     wiznet5k_obj.cs = cs;