minidump: Use the provided dump bitset

[mhorne]

Summary

When constructing the set of dumpable pages, use the bitset provided by
the state argument, rather than assuming vm_page_dump invariably. For
normal kernel minidumps this will be a pointer to vm_page_dump, but when
dumping the live system it will not.

To do this, the functions in vm_dumpset.h are extended to accept the
desired bitset as an argument. Note that this provided bitset is assumed
to be derived from vm_page_dump, and therefore has the same size.

[mhorne]

This is mostly mechanical. state->dump_bitset should be used inside each minidump_machdep.c, and vm_page_dump everywhere else. The one exception to this is powerpc's dumpsys_scan_pmap() method, which is extended to also accept a bitset argument.

[markj]

sys/amd64/amd64/pmap.c

4953

I think it'd be better to provide a helper which fixes the vm_page_dump parameter. e.g., rename dump_add_page() to vm_page_dump_add() and make have dump_add_page() just be vm_page_dump_add(vm_page_dump, pa). It feels a bit silly to force all of the interface consumers outside of minidumpsys() to specify the global context which exists solely for the minidumpsys() implementation.

[mhorne]

Add helpers to eliminate code churn outside of minidump_machdep.c.