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

Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Add USB device support ...

This patch adds support for USB devices. It uses
the Linux Kernel gadget API. Along with this patch
comes driver support for the Freescale (arc) USB OTG
Core and USB Device Firmware Update (DFU)
The serial gadget support is not working at the moment.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>