This patch modifies the Trusted Board Boot implementation to use
the new authentication framework, making use of the authentication
module, the cryto module and the image parser module to
authenticate the images in the Chain of Trust.

A new function 'load_auth_image()' has been implemented. When TBB
is enabled, this function will call the authentication module to
authenticate parent images following the CoT up to the root of
trust to finally load and authenticate the requested image.

The platform is responsible for picking up the right makefiles to
build the corresponding cryptographic and image parser libraries.
ARM platforms use the mbedTLS based libraries.

The platform may also specify what key algorithm should be used
to sign the certificates. This is done by declaring the 'KEY_ALG'
variable in the platform makefile. FVP and Juno use ECDSA keys.

On ARM platforms, BL2 and BL1-RW regions have been increased 4KB
each to accommodate the ECDSA code.

REMOVED BUILD OPTIONS:

  * 'AUTH_MOD'

Change-Id: I47d436589fc213a39edf5f5297bbd955f15ae867

This patch adds a CoT based on the Trusted Board Boot Requirements
document*. The CoT consists of an array of authentication image
descriptors indexed by the image identifiers.

A new header file with TBBR image identifiers has been added.
Platforms that use the TBBR (i.e. ARM platforms) may reuse these
definitions as part of their platform porting.

PLATFORM PORT - IMPORTANT:

Default image IDs have been removed from the platform common
definitions file (common_def.h). As a consequence, platforms that
used those common definitons must now either include the IDs
provided by the TBBR header file or define their own IDs.

*The NVCounter authentication method has not been implemented yet.

Change-Id: I7c4d591863ef53bb0cd4ce6c52a60b06fa0102d5

This major change pulls out the common functionality from the
FVP and Juno platform ports into the following categories:

*   (include/)plat/common. Common platform porting functionality that
typically may be used by all platforms.

*   (include/)plat/arm/common. Common platform porting functionality
that may be used by all ARM standard platforms. This includes all
ARM development platforms like FVP and Juno but may also include
non-ARM-owned platforms.

*   (include/)plat/arm/board/common. Common platform porting
functionality for ARM development platforms at the board
(off SoC) level.

*   (include/)plat/arm/css/common. Common platform porting
functionality at the ARM Compute SubSystem (CSS) level. Juno
is an example of a CSS-based platform.

*   (include/)plat/arm/soc/common. Common platform porting
functionality at the ARM SoC level, which is not already defined
at the ARM CSS level.

No guarantees are made about the backward compatibility of
functionality provided in (include/)plat/arm.

Also remove any unnecessary variation between the ARM development
platform ports, including:

*   Unify the way BL2 passes `bl31_params_t` to BL3-1. Use the
Juno implementation, which copies the information from BL2 memory
instead of expecting it to persist in shared memory.

*   Unify the TZC configuration. There is no need to add a region
for SCP in Juno; it's enough to simply not allow any access to
this reserved region. Also set region 0 to provide no access by
default instead of assuming this is the case.

*   Unify the number of memory map regions required for ARM
development platforms, although the actual ranges mapped for each
platform may be different. For the FVP port, this reduces the
mapped peripheral address space.

These latter changes will only be observed when the platform ports
are migrated to use the new common platform code in subsequent
patches.

Change-Id: Id9c269dd3dc6e74533d0e5116fdd826d53946dc8