arm64: dts: rockchip: add vcc_cam regulator to rock-3a

The Radxa ROCK3 Model A features a voltage regulator that provides
a 3V3 supply to the MIPI CSI connector. Add this regulator to the
device tree of the board.

Signed-off-by: Michael Riesch <michael.riesch@wolfvision.net>
Link: https://lore.kernel.org/r/20220712133204.2524942-1-michael.riesch@wolfvision.net


Signed-off-by: Heiko Stuebner <heiko@sntech.de>