ltq-atm: add Linux 5.0+ compatibility

Upstream commit 96d4f267e40f95 ("Remove 'type' argument from access_ok()
function") removes the first argument to access_ok.
Adjust the code so it builds with Linux 5.4.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Mathias Kresin <dev@kresin.me>

package/kernel/lantiq/ltq-atm/src/ltq_atm.c

@@ -289,9 +289,17 @@ static int ppe_ioctl(struct atm_dev *dev, unsigned int cmd, void *arg)
 		return -ENOTTY;
 
 	if ( _IOC_DIR(cmd) & _IOC_READ )
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5,0,0)
+		ret = !access_ok(arg, _IOC_SIZE(cmd));
+#else
 		ret = !access_ok(VERIFY_WRITE, arg, _IOC_SIZE(cmd));
+#endif
 	else if ( _IOC_DIR(cmd) & _IOC_WRITE )
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5,0,0)
+		ret = !access_ok(arg, _IOC_SIZE(cmd));
+#else
 		ret = !access_ok(VERIFY_READ, arg, _IOC_SIZE(cmd));
+#endif
 	if ( ret )
 		return -EFAULT;