docs: add inital lts doc
Ref: https://linaro.atlassian.net/browse/TFC-669
The initial LTS document was created as pdf and was maintained in a
shared folder location, to avoid pdf getting lost and trying to find
where it is we decided to have LTS details part of docs in TF-A.
This patch directly reflects the data from pdf attached to TFC-669.
Any improvements or amends to this will be done at later phases based
on LTS maintainers comments and agreements.
Change-Id: I1434c29f0236161d2a127596e2cc528bf4cc3e85
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
6 files changed
