Working on those XSAs made pretty apparent that there's a lot of redundancy,
requiring changes in too many separate places if e.g. adding / altering /
removing a hook. Obviously while dealing with that, some other, smaller
tidying opportunities turned up as well, which is what is being dealt with
here.

v2 addresses review feedback and includes a few new patches. See individual
patches for details.

01: XSM: make xsm_default_action() const-correct
02: XSM: convert "allow" (Flask: "access") parameters to bool
03: x86/mm: get_page_from_l1e() is PV-or-shadow-only
04: x86: restrict PHYSDEVOP_* when PV=n
05: XSM: make Argo hooks well-formed ones
06: XSM: fold xsm_{,un}map_domain_pirq() hooks
07: x86: type-correct last parameter of map_domain_pirq()
08: XSM: pass just SBDF to xsm_{,un}map_domain_irq()
09: XSM: fold xsm_{,un}map_domain_irq() hooks
10: XSM: fold xsm_{,un}bind_pt_irq() hooks
11: XSM: convert remaining event channel hooks
12: XSM: convert remaining domain-related hooks
13: XSM: convert remaining miscellaneous hooks
14: XSM: avoid fragile assumptions in xsm_fixup_ops()

Jan