mm, slub: extract get_partial() from new_slab_objects()

mm, slub: extract get_partial() from new_slab_objects()

The later patches will need more fine grained control over individual
actions in ___slab_alloc(), the only caller of new_slab_objects(), so this
is a first preparatory step with no functional change.

This adds a goto label that appears unnecessary at this point, but will be
useful for later changes.

Link: https://lkml.kernel.org/r/20210805152000.12817-8-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>