ARM: mvebu: use __pa_symbol in the mv98dx3236 platform SMP code

ARM: mvebu: use __pa_symbol in the mv98dx3236 platform SMP code

As we already did for Armada XP switch from virt_to_phys() to
__pa_symbol().

The reason for it was well explained by Mark Rutland so let's quote him:

"virt_to_phys() is intended to operate on the linear/direct mapping of
RAM.

__pa_symbol() is intended to operate on the kernel mapping, which may
not be in the linear/direct mapping on all architectures. e.g. arm64 and
x86_64 map the kernel image and RAM separately.

On 32-bit ARM the kernel image mapping is tied to the linear/direct
mapping, so that works, but as it's semantically wrong (and broken for
generic code), the DEBUG_VIRTUAL checks complain."

Fixes: db88977894ab ("arm: mvebu: support for SMP on 98DX3336 SoC")
Cc: <stable@vger.kernel.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>