media: atomisp: keep the ISP powered on when setting it

The current code causes ISP2401 to power down and never return
back to live, causing the driver to crash.

Fix it by commenting out the bad code. It should be noticed that
the Yocto Aero code has something similar to it.

Maybe the issue is related to an ISP bug (or maybe PM is
controlled on a different way for this hardware).

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>