feat(plat/st): manage io_policies with FCONF

Introduced IO policies management through the trusted
boot firmware config device tree for UUID references.

Change-Id: Ibeeabede51b0514ebba26dbbdae587363b2aa0a7
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
6 files changed