[media] omap3isp: resizer: Protect against races when updating crop

When updating the crop rectangle during streaming, the IRQ handler will
reprogram the resizer after the current frame. A race condition
currently exists between the set selection operation and the IRQ
handler: if the set selection operation is called twice in a row and the
IRQ handler runs only during the second call, it could reprogram the
hardware with partially updated values. Use a spinlock to protect
against that.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>