linux-phytec-ti

prueth: fix irq cleanup

When prueth device is stopped, the irq is freed only for the
last device. This results in irq request still pending for the
first device. This patch fixes the issue.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Jacob Stiffler <j-stiffler@ti.com>