ARM: dts: msm: camera: enable actuator for front camera for 8994

add entry for actuator in camera node for front camera to enable
actuator, because front camera ov4688 for 8994 devices have
support for actuator driver

Change-Id: I2b51b006b75ccd56c256525ac2899c2bdc63121b
Signed-off-by: Vasko Kalanoski <vaskok@codeaurora.org>