arm: mach-orion5x: use IOMEM() for base address definitions

We now define all virtual base address constants using IOMEM() so that
those are naturally typed as void __iomem pointers, and we do the
necessary adjustements in the mach-orion5x code.

Note that we introduce a few temporary additional "unsigned long"
casts when calling into plat-orion functions. Those are removed by
followup patches converting plat-orion functions to void __iomem
pointers as well.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>