refactor(imx): console runtime switch on bl31 exit

Flush the FIFO before switching to runtime. This is so that there are
no lingering chars in the FIFO when we move to the runtime console.

TF-A plans to refactor the console_Switch_state(CONSOLE_FLAG_RUNTIME)
and console_flush() calls and make them the last calls in bl31_main()
(before BL31 exits). Until then they are being left as the last calls
in bl31_plat_runtime_setup() for testing before refactoring.

This patch affects the Freescale/NXP SoCs imx93, imx8qm and imx8qx.

Change-Id: Iece74579e1d15eeeb8279db0c53d74bce45545bd
Signed-off-by: Salman Nabi <salman.nabi@arm.com>
3 files changed