doc: sl-mx8mm: Update the NXP TF-A source reference

Use the latest version of the NXP TF-A code and add a note about
quirks with GCC 12.

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Convert Note: to ..note::
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
1 file changed