docs(changelog): add subsections for STM32MP25

The STM32MP2 family has 3 different types of SoCs (STM32MP25, STM32MP23
and STM32MP21). For the moment only STM32MP25 is partly supported in
TF-A. Add a dedicated subsections for STM32MP25. The other ones will be
added later. The same is done for FDTS scope.

Signed-off-by: Yann Gautier <[email protected]>
Signed-off-by: Nicolas Le Bayon <[email protected]>
Change-Id: Ia18824a7b649bcd1ffa631e3aa0ecb3fd0b2d038
1 file changed