DO_NOT_MERGE dt-bindings: soc: add Foobar SoC memory controller

Add bindings for an example SoC memory controller that implements CBQRI.

Co-developed-by: Adrien Ricciardi <aricciardi@baylibre.com>
Signed-off-by: Adrien Ricciardi <aricciardi@baylibre.com>
Signed-off-by: Drew Fustini <dfustini@baylibre.com>