Currently I'm unable to boot initramfs image with `console=ttyS0,115200`
kernel commandline as the kernel commandline mangling resets kernel
commandline if there is no `root=` option provided, efectively clearing
whatever I pass to the kernel, making the `root=` option mandatory.
So if the kernel commandline mangling is not appropriate just leave the
kernel commandline as it is.
Signed-off-by: Petr Štetiar <ynezz@true.cz>