powerpc/boot: fix the early OPAL console wrappers

[Michael Ellerman]

On Wed, 2016-11-23 at 02:55:13 UTC, Oliver O'Halloran wrote:
> When configured with CONFIG_PPC_EARLY_DEBUG_OPAL=y the kernel expects
> the OPAL entry and base addresses to be passed in r8 and r9
> respectively. Currently the wrapper does not attempt to restore these
> values before entering the decompressed kernel which causes the kernel
> to branch into whatever happens to be in r9 when doing a write to the
> OPAL console in early boot.
> 
> This patch adds a platform_ops hook that can be used to branch into the
> new kernel. The OPAL console driver patches this at runtime so that if
> the console is used it will be restored just prior to entering the
> kernel.
> 
> Fixes: 656ad58ef19e
> Signed-off-by: Oliver O'Halloran <oohall at gmail.com>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/a1ff57416af9a7971a801d553cd53e

cheers