x86: Add a function to assign IRQ numbers to PCI device

Add a function to assign an IRQ number to PCI device's interrupt
line register in its configuration space, so that the PCI device
can have its interrupt working under PIC mode after OS boots up.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
2 files changed