An upcoming patch to use the bitset macros for tracking vm page
dump information could conceivably need more than INT_MAX bits.
Expand the bit type to long so that the extra range is available
on 64-bit platforms where it would most likely be needed.
CPUSET_COUNT and DOMAINSET_COUNT are also modified to remain of
type `int`.
Reviewed by: kib, markj
Approved by: scottl (implicit)
MFC after: 1 week
Sponsored by: Ampere Computing, Inc.
Differential Revision: https://reviews.freebsd.org/D26190
ab369b5980