PCI: mobiveil: Move IRQ chained handler setup out of DT parse

The irq_set_chained_handler_and_data() call is not dependent on device
tree firmware so it should be moved out of the DT parsing function for
clarity.

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
[lorenzo.pieralisi@arm.com: rewritten commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Minghuan Lian <Minghuan.Lian@nxp.com>
Reviewed-by: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>