mx31moboard: change initial reset status for robot microcontollers

We want the microcontrollers to be held in reset during kernel boot.

We also set the turretcam as the default camera since it is present on all
marxbots.

Signed-off-by: Valentin Longchamp <valentin.longchamp@epfl.ch>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>