MFC r276321, r276404, r276407 and r276799:
Various XHCI fixes and improvements:

• Improve and fix MSI interrupt allocation, setup and release.
• Add missed flushing of data which can happen when "xhci_configure_mask()" is called from "xhci_configure_reset_endpoint()". Ensure the 3-strikes error feature is always enabled except for ISOCHRONOUS transfers.
• Allow systems having a page size greater than 4K to use fewer scatter-gather XHCI TRB entries for its payload data. The XHCI controller can handle at least 65536 bytes per scatter-gather list entry.