ARM: mvebu: conditionalize Armada 375 SMP workaround

ARM: mvebu: conditionalize Armada 375 SMP workaround

The Armada 375 SMP workaround only needs to be applied to the Z1
revision of the SoC. The A0 and later revisions have been fixed, and
no longer need this workaround.

Note that the initialization of the SMP workaround is delayed from
->smp_prepare_cpus() to ->smp_boot_secondary() because when
->smp_prepare_cpus() is called, the early initcalls have not be
called, so the mvebu-soc-id mechanism is not operational. Since the
workaround is anyway not needed before the secondary CPU is started,
we can delay its implementation until the ->smp_boot_secondary() call.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1399302326-6917-5-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>