net: wl12xx: care for optional operations

->init and ->reset are optional - at least
sdio.c doesn't implement them - so allow those
pointers to be NULL.
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>

drivers/net/wireless/wl12xx/io.c

@@ -128,12 +128,14 @@ EXPORT_SYMBOL_GPL(wl1271_set_partition);
 
 void wl1271_io_reset(struct wl1271 *wl)
 {
-	wl->if_ops->reset(wl);
+	if (wl->if_ops->reset)
+		wl->if_ops->reset(wl);
 }
 
 void wl1271_io_init(struct wl1271 *wl)
 {
-	wl->if_ops->init(wl);
+	if (wl->if_ops->init)
+		wl->if_ops->init(wl);
 }
 
 void wl1271_top_reg_write(struct wl1271 *wl, int addr, u16 val)