media: dw9807-vcm: Smooth the first user movement of the lens

The power up/down sequence is already ramped. Extend this to
the first user movement as well, as this will generally avoid
the "tick" noises due to rapid movements and overshooting.
Subsequent movements are generally smaller and so don't cause
issues.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>