Fix the inconsistencies in bl1_tbbr_image_descs[] ...

This patch fixes inconsistencies in bl1_tbbr_image_descs[]
and miscellaneous fixes in Firmware Update code.

Following are the changes:
* As part of the original FWU changes, a `copied_size`
  field was added to `image_info_t`. This was a subtle binary
  compatibility break because it changed the size of the
  `bl31_params_t` struct, which could cause problems if
  somebody used different versions of BL2 or BL31, one with
  the old `image_info_t` and one with the new version.
  This patch put the `copied_size` within the `image_desc_t`.
* EXECUTABLE flag is now stored in `ep_info.h.attr` in place
  of `image_info.h.attr`, associating it to an entrypoint.
* The `image_info.image_base` is only relevant for secure
  images that are copied from non-secure memory into secure
  memory. This patch removes initializing `image_base` for
  non secure images in the bl1_tbbr_image_descs[].
* A new macro `SET_STATIC_PARAM_HEAD` is added for populating
  bl1_tbbr_image_descs[].ep_info/image_info.h members statically.
  The version, image_type and image attributes are now
  populated using this new macro.
* Added PLAT_ARM_NVM_BASE and PLAT_ARM_NVM_SIZE to avoid direct
  usage of V2M_FLASH0_XXX in plat/arm/common/arm_bl1_fwu.c.
* Refactoring of code/macros related to SECURE and EXECUTABLE flags.

NOTE: PLATFORM PORTS THAT RELY ON THE SIZE OF `image_info_t`
      OR USE the "EXECUTABLE" BIT WITHIN `image_info_t.h.attr`
      OR USE THEIR OWN `image_desc_t` ARRAY IN BL1, MAY BE
      BROKEN BY THIS CHANGE. THIS IS CONSIDERED UNLIKELY.

Change-Id: Id4e5989af7bf0ed263d19d3751939da1169b561d

FWU: Add Generic Firmware Update framework support in BL1 ...

Firmware update(a.k.a FWU) feature is part of the TBB architecture.
BL1 is responsible for carrying out the FWU process if platform
specific code detects that it is needed.

This patch adds support for FWU feature support in BL1 which is
included by enabling `TRUSTED_BOARD_BOOT` compile time flag.

This patch adds bl1_fwu.c which contains all the core operations
of FWU, which are; SMC handler, image copy, authentication, execution
and resumption. It also adds bl1.h introducing #defines for all
BL1 SMCs.

Following platform porting functions are introduced:

int bl1_plat_mem_check(uintptr_t mem_base, unsigned int mem_size,
unsigned int flags);
	This function can be used to add platform specific memory checks
	for the provided base/size for the given security state.
	The weak definition will invoke `assert()` and return -ENOMEM.

__dead2 void bl1_plat_fwu_done(void *cookie, void *reserved);
	This function can be used to initiate platform specific procedure
	to mark completion of the FWU process.
	The weak definition waits forever calling `wfi()`.

plat_bl1_common.c contains weak definitions for above functions.

FWU process starts when platform detects it and return the image_id
other than BL2_IMAGE_ID by using `bl1_plat_get_next_image_id()` in
`bl1_main()`.

NOTE: User MUST provide platform specific real definition for
bl1_plat_mem_check() in order to use it for Firmware update.

Change-Id: Ice189a0885d9722d9e1dd03f76cac1aceb0e25ed