powerpc/64s: Remove SAO feature from Power9 DD1

[ Upstream commit ca80d5d0a8175c9be04cfbce24180b8f5e0a744b ]

Power9 DD1 does not implement SAO. Although it's not widely used, its presence
or absence is visible to user space via arch_validate_prot() so it's moderately
important that we get the value right.

Fixes: 7dccfbc3 ("powerpc/book3s: Add a cpu table entry for different POWER9 revs")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>