ti: k3: common: Enable MMU using xlat_tables_v2 library

This library will be used to properly set up mappings from different
bootloaders at different exception levels. It ensures that memory mapped
devices such as UARTs are still accessible and memory regions have the
correct access permissions.

Signed-off-by: Benjamin Fair <b-fair@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Andrew F. Davis <afd@ti.com>