Add support for the Artesyn MVME7100 Single Board Computer.

The MVME7100 is a 6U form factor VME64 computer with:

    - A two e600 cores Freescale MPC8641D CPU
    - 2 GB of DDR2 onboard memory
    - Four Gigabit Ethernets
    - Five 16550 compatible UARTs
    - One USB 2.0 port
    - Two PCI/PCI eXpress Mezzanine Card (PMC/XMC) Slots
    - A DS1375 Real Time Clock (RTC)
    - 512 KB of Non-Volatile Memory (NVRAM)
    - Two 64 KB EEPROMs
    - 128 MB NOR and 4/8 GB NAND Flash

This patch is based on linux-4.7-rc1 and has been only boot tested.

Limitations:
    This patch covers only models 171 and 173
    No plans to support CPLD timers

Know issues:
    All four PHYs work in polling mode

Configuration is missing for:
    PCI IDSEL and PCI Interrupt definition

Support is missing for:
    Cache and memory controllers (which are very similar to the 85xx ones
        but right now I don't know if we can re-use their support)
    Watchdog, USB, NVRAM, NOR, NAND, EEPROMs, VME, PMC/XMC and RTC

Signed-off-by: Alessio Igor Bogani <alessio.bogani@elettra.eu>
Signed-off-by: Scott Wood <oss@buserror.net>

U-boots more recent than when ppcboot.h was forked allow the board config
file to enable additional ethernet ports explicitly, rather than
using a hardcoded list of targets.  This allows bootwrapper platform
files to do the same.

Fortunately, nothing after the ethernet addresses is of interest to
cuboot platforms, so the inevitable mismatches won't be too catastrophic.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

This file describes the bd_t struct, which is used by old versions of
U-boot to pass information to the kernel.  Platform code that needs to
interoperate with such firmware can use this; it should not be used for
anything new.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>