New round of my IXP42x patches

[Krzysztof Halasa]

I've fixed the 3 remaining patches:
1.  Fix error handling with malloc, memalign etc. Introduce xmemalign().

    The idea is to panic() when there is no memory available for normal
    operation. Exception: code which can consume arbitrary amount of RAM
    (example: files allocated in ramfs) must report error instead of
    panic().

    This patch also fixes code which didn't check for NULL from malloc()
    etc.

    Usage: malloc(), xmemalign() return NULL when out of RAM.
    xmalloc(), xmemalign() always return non-NULL or panic().

(I've removed the clkdev changes as requested)

2.  ARM: support big/little endian switching in "bootz".
    I've renamed CONFIG_BOOTZ_ENDIANNESS_SWITCH to
                 CONFIG_BOOT_ENDIANNESS_SWITCH anticipating support for
    endianness switching for bootm and bootu, either automatic or with
    additional parameter.

3. ARM: Add support for IXP4xx CPU and for Goramo Multilink router
   platform.

Fixed the memalign() -> xmemalign() usage in IXP4xx Ethernet driver.

I'm currently using Barebox with these three patches applied.
-- 
Krzysztof Halasa