pmap_kenter_temporary() uses the fixed-size crashdump map. Moreover,
the ACPI table-mapping code was not verifying that the table fits in
this map, so with large tables we could clobber adjacent mappings. The
use of the crashdump map here seems to predate support for "preinit"
mappings on amd64 and i386; I can't see any reason not to use
pmap_mapbios() now, like arm64 does.
Also remove an unused "offset" parameter from map_table() on arm64.