README.md: Update TI URLs to product landing pages
README.md: Update TI URLs to product landing pages

Currently we point to an individual SoCs product page, each OP-TEE
flavor works across an entire SoC family, so point the flavor info
to the family landing page instead.

Signed-off-by: Andrew F. Davis <a6dfde0ec5c5124d26ab0cb4f9ab9a758dee1d6f@ti.com>
Acked-by: Jerome Forissier <ced78d268b4c9a0a20a59a9feeebd2ad90da03d3@linaro.org>

pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os