[media] omap3isp: ccdc: Simplify ccdc_lsc_is_configured()

Use a local variable to avoid the duplicate spin_unlock_irqrestore()
call.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Enrico Butera <ebutera@users.sourceforge.net>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>