powerpc/64s: Allow control of RFI flush via debugfs

[Michael Ellerman]

On Tue, 2018-01-16 at 11:24:31 UTC, Michael Ellerman wrote:
> Expose the state of the RFI flush (enabled/disabled) via debugfs, and
> allow it to be enabled/disabled at runtime.
> 
> eg: $ cat /sys/kernel/debug/powerpc/rfi_flush
>     1
>     $ echo 0 > /sys/kernel/debug/powerpc/rfi_flush
>     $ cat /sys/kernel/debug/powerpc/rfi_flush
>     0
> 
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
> Reviewed-by: Nicholas Piggin <npiggin at gmail.com>

Applied to powerpc fixes.

https://git.kernel.org/powerpc/c/236003e6b5443c45c18e613d2b0d77

cheers