wlcore: sdio: check for valid platform device data before suspend

the wl pointer can be null In case only wlcore_sdio is probed while
no WiLink module is successfully probed, as in the case of mounting a
wl12xx module while using a device tree file configured with wl18xx
related settings.
In this case the system was crashing in wl1271_suspend() as platform
device data is not set.
Make sure wl the pointer is valid before using it.

Signed-off-by: Eyal Reizer <eyalr@ti.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ti/wlcore/sdio.c

@@ -399,6 +399,11 @@ static int wl1271_suspend(struct device *dev)
 	mmc_pm_flag_t sdio_flags;
 	int ret = 0;
 
+	if (!wl) {
+		dev_err(dev, "no wilink module was probed\n");
+		goto out;
+	}
+
 	dev_dbg(dev, "wl1271 suspend. wow_enabled: %d\n",
 		wl->wow_enabled);