[RFC/PATCH 0/7] Powerpc MSI Implementation

[Michael Ellerman]

Another cut at a Powerpc MSI implementation. This is working with the MPIC
backend, still haven't tested the RTAS backend.

Things I remember changing since last time:
 * Fixed a few bugs pointed out by Jake.
 * We discover the MPIC magic address via the PCI config space rather than
   hard coding it.
 * We reuse pdev->irq in the MPIC backend for now. This is nasty but works.
 * Moved msi_info into the pci_dev. This is ugly, but not sure where else
   we can put it, pci_dn is no longer an option.
 * Added a place holder msi_info->msix_base pointer.
 * Still haven't implement raw MSIX enabled, todo.
 * Removed the msi_info->priv. No on was using it, can always put it back.
 * Added lots of debugging in anticipation of getting some firware to test on.
 ...

cheers