feat(plat/imx/imx8m/imx8mp): add initial definition to facilitate FIP layout

Adds a number of definitions consistent with the established RSB3720
equivalents specifying number of io_handles and block devices.

Signed-off-by: Ying-Chun Liu (PaulLiu) <paulliu@debian.org>
Change-Id: I401e48216d67257137351ee4d0b98904a76fa789
1 file changed