Nodemasks now pull linux/numa.h for MAX_NUMNODES and NUMA_NO_NODE
macros. This series makes numa.h depending on nodemasks, so we hit
a circular dependency.

Nodemasks library is highly employed by NUMA code, and it would be
logical to resolve the circular dependency by making NUMA headers
dependent nodemask.h.

Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

sched.h, which defines task_struct, needs nodemask_t - but sched.h is a
frequently used header and ideally shouldn't be pulling in any more code
that it needs to.

This splits out nodemask_types.h which has the definition sched.h needs,
which will avoid a circular header dependency in the alloc tagging patch
series, and as a bonus should speed up kernel build times.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>