irqchip: vic: Parse interrupt and resume masks from device tree

This patch extends vic_of_init to parse valid interrupt sources
and resume sources masks from device tree.

If mask values are not specified in device tree, all sources
are assumed to be valid, as before this patch.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>