wifi: zd1211rw: fix potential memory leak in __zd_usb_enable_rx()

The memory allocated for urbs with kcalloc() is not freed on any error
path. Fix that by freeing it in the error path.

Fixes: e85d0918b54f ("[PATCH] ZyDAS ZD1211 USB-WLAN driver")
Signed-off-by: Abdun Nihaal <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Johannes Berg <[e-mail]>

drivers/net/wireless/zydas/zd1211rw/zd_usb.c

···
 	if (urbs) {
 		for (i = 0; i < RX_URBS_COUNT; i++)
 			free_rx_urb(urbs[i]);
+		kfree(urbs);
 	}
 	return r;
 }