Add support for IRQ combiners in the Top-level Control and Status
Registers (TCSR) hardware block in Qualcomm Technologies chips.
The first patch fixes IRQ probe deferral by allowing platform_device
IRQ resources to be re-initialized if the ACPI core failed to find
the IRQ domain during ACPI bus scan.
The second patch adds support for ResourceSource/IRQ domain mapping
when using Extended IRQ Resources with a specific ResourceSource.
These changes are conditional on the ACPI_GENERIC_GSI config.
The third patch takes advantage of the new capabilities to implement
the driver for the IRQ combiners.
Tested on top of v4.9-rc4.
Changes V6 -> V7:
* Consolidate changes for ResourceSource/IRQ domain mapping to the same
source file implementing the generic GSI support, making it conditional
* Eliminate some code duplication by implementing acpi_register_gsi in
terms of the new acpi_register_irq API.