sc1200_wdt: Fix oops

If loaded with isapnp = 0 the driver explodes. This is catching
people out now and then. What should happen in the working case is
a complete mystery and the code appears terminally confused, but we
can at least make the error path work properly.

Signed-off-by: Alan Cox <[e-mail]>
Reviewed-by: Guenter Roeck <[e-mail]>
Signed-off-by: Wim Van Sebroeck <[e-mail]>
Partially-Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=53991

drivers/watchdog/sc1200wdt.c

···
 #if defined CONFIG_PNP
 	/* now that the user has specified an IO port and we haven't detected
 	 * any devices, disable pnp support */
+	if (isapnp)
+		pnp_unregister_driver(&scl200wdt_pnp_driver);
 	isapnp = 0;
-	pnp_unregister_driver(&scl200wdt_pnp_driver);
 #endif
 
 	if (!request_region(io, io_len, SC1200_MODULE_NAME)) {