tty: hvc: fix return value of __setup handler

__setup() handlers should return 1 to indicate that the boot option
has been handled or 0 to indicate that it was not handled.
Add a pr_warn() message if the option value is invalid and then
always return 1.

Link: lore.kernel.org/r/[email protected]
Fixes: 86b4056 ("tty: replace strict_strtoul() with kstrtoul()")
Cc: Jingoo Han <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Julian Wiedmann <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: [email protected]
Reported-by: Igor Zhbanov <[email protected]>
Signed-off-by: Randy Dunlap <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: rddunlap

drivers/tty/hvc/hvc_iucv.c

@@ -1417,7 +1417,9 @@ static int __init hvc_iucv_init(void)
  */
 static	int __init hvc_iucv_config(char *val)
 {
-	 return kstrtoul(val, 10, &hvc_iucv_devices);
+	if (kstrtoul(val, 10, &hvc_iucv_devices))
+		pr_warn("hvc_iucv= invalid parameter value '%s'\n", val);
+	return 1;
 }