media: adv748x: afe: Select input port when initializing AFE

When moving the input selection to adv748x_reset() it was missed that
during probe the device is reset _before_ the initialization and parsing
of DT by the AFE subdevice. This can lead to the wrong input port (in
case it's not port 0) being selected until the device is reset for the
first time.

Fix this by restoring the call to adv748x_afe_s_input() in the AFE
initialization while also keeping it in the adv748x_reset().

Fixes: c30ed81a ("media: adv748x: afe: Select input port when device is reset")
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>