Various improvements/cleanups on the linker scripts ...

- Check at link-time that bootloader images will fit in memory
    at run time and that they won't overlap each other.
  - Remove text and rodata orphan sections.
  - Define new linker symbols to remove the need for platform setup
    code to know the order of sections.
  - Reduce the size of the raw binary images by cutting some sections
    out of the disk image and allocating them at load time, whenever
    possible.
  - Rework alignment constraints on sections.
  - Remove unused linker symbols.
  - Homogenize linker symbols names across all BLs.
  - Add some comments in the linker scripts.

Change-Id: I47a328af0ccc7c8ab47fcc0dc6e7dd26160610b9

fvp: Remove unnecessary initializers ...

Global and static variables are expected to be initialised to zero
by default.  This is specified by the C99 standard. This patch
removes some unnecessary initialisations of such variables.

It fixes a compilation warning at the same time:
  plat/fvp/bl31_plat_setup.c:82:3: warning: missing braces around
  initializer [-Wmissing-braces]
     section("tzfw_coherent_mem"))) = {0};
     ^
  plat/fvp/bl31_plat_setup.c:82:3: warning: (near initialization for
  ‘ns_entry_info[0]’) [-Wmissing-braces]

Note that GCC should not have emitted this warning message in the
first place.  The C Standard permits braces to be elided around
subaggregate initializers.  See this GCC bug report:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53119

Change-Id: I13cb0c344feb9803bca8819f976377741fa6bc35

Do not enable CCI on Foundation FVP ...

- The Foundation FVP only has one cluster and does not have
  CCI.

Change-Id: If91e81ff72c52e448150089c4cfea3e4d6ae1232

ARMv8 Trusted Firmware release v0.2