media: nxp: imx8-isi: Remove 300ms sleep after enabling channel

media: nxp: imx8-isi: Remove 300ms sleep after enabling channel

The current implementation of the mxc_isi_channel_enable() function has
a hard 300ms sleep. This was copied from the NXP BSP, which has since
dropped the sleep in a commit that implied the delay was meant to wait
for the sensor to be "stable". As the sensor is started after the ISI,
the delay won't affect sensor operation. Drop it.

Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>