arm: conditionally support regular ARM instructions

Until now, all ARM processors supported the original ARM mode. However,
the Cortex-M variant do not support them, and support only Thumb/Thumb2 modes.

So, make a Kconfig option for ARM support and use it.

Signed-off-by: Guido Martínez <guido@vanguardiasur.com.ar>
arm: update processor types

Add the Cortex M3 variant. This microcontrollers don't support regular
ARM instructions and don't have an MMU.

Signed-off-by: Guido Martínez <guido@vanguardiasur.com.ar>
toolchain: allow for stupid toolchains

check_arm_abi builds a test C file to check that the toolchain is
working correctly, with the output redirected to /dev/null.

However, some toolchains (OSELAS 2013.12.2, for instance) foolishly
append ".gdb" to the output filename for an intermediate file, causing
an attempt to write to /dev/null.gdb, which obviously fails.

Fix this by adding an option to skip this check, so it can be selected
in the OSELAS toolchain.

Signed-off-by: Guido Martínez <guido@vanguardiasur.com.ar>
toolchain-external: add OSELAS Cortex-M3 toolchain

Binary toolchain for Cortex-M3 processor based on GCC 4.8.2.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
board: Add all the specific stuff for the CIAA NXP LPC4337

This commits adds a board directory to contain all the board-specific
configuration and setup. For now, we only have some rootfs files
and the busybox configuration.

If we ever need custom patches, or custom configuration, this where
they belong. Please, keep the tree green and clean.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
configs: Add CIAA NXP LPC4337 config

This configuration builds the OSELAS Cortex-M3 toolchain, and the CIAA-hosted
U-Boot and Linux kernel. It produces a u-boot.bin and a uImage images.

The init process only runs a shell and avoids any System-V scripts
(see /etc/inittab). Therefore, don't bother adding init.d script.

The following packages have been added:

  * strace
  * i2c-tools
  * memtester
  * mii-dia

Read board/ciaa/lpc4337/README for details

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>