Introduce BTI support in ROMLIB ...

When TF-A is compiled with BTI enabled, the branches in the ROMLIB
jumptable must be preceded by a "bti j" instruction.

Moreover, when the additional "bti" instruction is inserted, the
jumptable entries have a distance of 8 bytes between them instead of 4.
Hence, the wrappers are also modified accordinly.

If TF-A is compiled without BTI enabled, the ROMLIB jumptable and
wrappers are generated as before.

Change-Id: Iaa59897668f8e59888d39046233300c2241d8de7
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>

romlib: Add platform specific jump table list ...

This patch allows platforms to define their
own jump table list for library at ROM. The
file has the list of functions to be used
from library at ROM. It can also include
other list files.

Change-Id: I721c35d7dad3dcadbb3a7f3277bfd5d3e1f6e00a
Signed-off-by: Sathees Balya <sathees.balya@arm.com>

Add support for romlib in the build system ...

Romlib is a new image that is stored in ROM and contains the code of
several libraries that can be shared between different images. All
the functions within in the library are accessed using a jump table
which allows to update the romlib image whithout changing the binary
compatibility. This jump table can be also stored in RAM and it can
allow to patch a romlib with potential bugs fixes..

Change-Id: If980ccdaca24b7aaca900e32acc68baf6f94ab35
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>