block/keyslot-manager: use kvfree_sensitive()

Make blk_ksm_destroy() use the kvfree_sensitive() function (which was
introduced in v5.8-rc1) instead of open-coding it.

Signed-off-by: Eric Biggers <[e-mail]>
Signed-off-by: Jens Axboe <[e-mail]>

block/keyslot-manager.c

···
 	if (!ksm)
 		return;
 	kvfree(ksm->slot_hashtable);
-	memzero_explicit(ksm->slots, sizeof(ksm->slots[0]) * ksm->num_slots);
-	kvfree(ksm->slots);
+	kvfree_sensitive(ksm->slots, sizeof(ksm->slots[0]) * ksm->num_slots);
 	memzero_explicit(ksm, sizeof(*ksm));
 }
 EXPORT_SYMBOL_GPL(blk_ksm_destroy);