boards: mimxrt1160_evk: Refactor flexspi partition definition

Flexspi partition definition is shared between both cm4 and cm7 core.
Refactor it to be in shared dtsi file. This will ensure that both cores
share the same partition information, for dual core operation.

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>
3 files changed