slab: remove defer_deactivate_slab()

slab: remove defer_deactivate_slab()

There are no more cpu slabs so we don't need their deferred
deactivation. The function is now only used from places where we
allocate a new slab but then can't spin on node list_lock to put it on
the partial list. Instead of the deferred action we can free it directly
via __free_slab(), we just need to tell it to use _nolock() freeing of
the underlying pages and take care of the accounting.

Since free_frozen_pages_nolock() variant does not yet exist for code
outside of the page allocator, create it as a trivial wrapper for
__free_frozen_pages(..., FPI_TRYLOCK).

Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Hao Li <hao.li@linux.dev>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>