x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces

x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces

Convert IOAPIC driver to support and use hierarchical irqdomain
interfaces.  It's a little big, but would break bisecting if we split
it into multiple patches.

Fold in a patch from Andy Shevchenko <[email protected]>
to make it bisectable.
http://lkml.org/lkml/2014/12/10/622

Signed-off-by: Jiang Liu <[email protected]>
Tested-by: Joerg Roedel <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Cc: Sander Eikelenboom <[email protected]>
Cc: David Vrabel <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: [email protected]
Cc: Bjorn Helgaas <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Yinghai Lu <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dimitri Sivanich <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Pavel Machek <[email protected]>
Cc: Grant Likely <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: David Cohen <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>