feat(plat/arm): add GPT parser support

Added GPT parser support in BL2 for Arm platforms to get the entry
address and length of the FIP in the GPT image.

Also, increased BL2 maximum size for FVP platform to successfully
compile ROM-enabled build with this change.

Verified this change using a patch:

Change-Id: Ie8026db054966653b739a82d9ba106d283f534d0
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
8 files changed