docs(st): introduce STM32MP_RECONFIGURE_CONSOLE

This flag will be used in BL32, to reconfigure UART parameters for
the early or crash console. By default, it is zero, as UART is
already configured in BL2.

Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Change-Id: I7b28ff489479ab04a2fade027933524cdd36e959
1 file changed