Add initial symbols required for i.MX 7 boards, based on devices
available on TechNexion PICO-PI-IMX7D board.
Signed-off-by: Lech Perczak <lech.perczak@gmail.com>
[pepe2k@gmail.com: refreshed subtarget kernel config]
Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>