[media] davinci: vpif: add check for genuine interrupts in the isr

As the same interrupt is shared between capture and display devices,
sometimes we get isr calls where the interrupt might not genuinely belong
to capture or display. Hence, add a condition in the isr to check for
interrupt ownership and channel number to make sure we do not
service wrong interrupts.

Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com>
Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>