Update related to new optee linux driver implementation

Change-Id: Ic2034c1967ed3c4edaca267467efe3c3fa1037a9
Signed-off-by: Cedric Chaumont <cedric.chaumont@st.com>

First pass for code review
New design based on platform device driver
Validated on stm h410
4 ST failing tests (w/o optee-os patches) 1005, 6010, 7505, 7633
arm64 support needs to be updated
Might be a personal taste, but I think it's more easy to read when you have space between ?= ... same comment applies to the rest of the file.