media: i2c: ds90ub960: Fix logging SP & EQ status only for UB9702

UB9702 does not have SP and EQ registers, but the driver uses them in
log_status(). Fix this by separating the SP and EQ related log_status()
work into a separate function (for clarity) and calling that function
only for UB960.

Cc: stable@vger.kernel.org
Fixes: afe267f2 ("media: i2c: add DS90UB960 driver")
Reviewed-by: Jai Luthra <jai.luthra@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>