mips: Return proper error code from console ->setup() hook

For unifying console ->setup() handling, which is poorly documented,
return error code, rather than non-zero arbitrary number.

Signed-off-by: Andy Shevchenko <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Acked-by: Thomas Bogendoerfer <[email protected]>
Signed-off-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: andy-shev

arch/mips/fw/arc/arc_con.c

@@ -28,7 +28,9 @@ static void prom_console_write(struct console *co, const char *s,
 
 static int prom_console_setup(struct console *co, char *options)
 {
-	return !(prom_flags & PROM_FLAG_USE_AS_CONSOLE);
+	if (prom_flags & PROM_FLAG_USE_AS_CONSOLE)
+		return 0;
+	return -ENODEV;
 }
 
 static struct console arc_cons = {