docs: removing references to GitHub ...

Change-Id: Ibdee91ad337ee362872924d93e82f5b5e47e63d9
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>

doc: Reformat platform port documents ...

The platform port documents are not very standardised right now and
they don't integrate properly into the document tree so:

1) Make sure each port has a proper name and title (incl. owner)
2) Correct use of headings, subheadings, etc in each port
3) Resolve any naming conflicts between documents

Change-Id: I4c2da6f57172b7f2af3512e766ae9ce3b840b50f
Signed-off-by: Paul Beesley <paul.beesley@arm.com>

Documentation for Versatile Express Fixed Virtual Platforms ...

This documentation contains information about the boot sequence,
code location and build procedure for fvp_ve platform.

Change-Id: I339903f663cc625cfabc75ed8e4accb8b2c3917c
Signed-off-by: Usama Arif <usama.arif@arm.com>