Update path to printk control variable

From https://github.com/gobolinux/Installer/blob/master/bin/Installer#L28:
```
 printk=$(cat /System/Kernel/Status/sys/kernel/printk)
```

Recent kernels no longer store the printk control variable on that file.  `/proc/sys/kernel/printk` and `/sys/module/printk/parameters/*` is where it lives now.

Bug reported by user "crazy" from #redcorelinux