refactor(st): replace STM32MP_EARLY_CONSOLE with EARLY_CONSOLE

Now that EARLY_CONSOLE is generic, use it instead of the ST flag.
Remove stm32mp_setup_early_console() calls as it is done in common TF-A
code.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: Icac29b62a6267303cb5c679d15847c013ead1d23
7 files changed