refactor: first cactus SP to drop uart

The first cactus SP was using a uart device to
serve as a validation for the device memory regions.
Currently, there are other uses that serve this test.
As such dropping the uart device from the manifest, and
configuring SPs to always use FFA_CONSOLE_LOG.

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: I0ee35bfca7a885f5adc112964edeb627bb659fc0
5 files changed