libceph: nuke unused fields and functions

Either unused or useless:

    osdmap->mkfs_epoch
    osd->o_marked_for_keepalive
    monc->num_generic_requests
    osdc->map_waiters
    osdc->last_requested_map
    osdc->timeout_tid

    osd_req_op_cls_response_data()

    osdmap_apply_incremental() @msgr arg

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
diff --git a/include/linux/ceph/osdmap.h b/include/linux/ceph/osdmap.h
index 777a294..ce7a41a 100644
--- a/include/linux/ceph/osdmap.h
+++ b/include/linux/ceph/osdmap.h
@@ -123,7 +123,6 @@
 struct ceph_osdmap {
 	struct ceph_fsid fsid;
 	u32 epoch;
-	u32 mkfs_epoch;
 	struct ceph_timespec created, modified;
 
 	u32 flags;         /* CEPH_OSDMAP_* */
@@ -205,9 +204,8 @@
 }
 
 extern struct ceph_osdmap *ceph_osdmap_decode(void **p, void *end);
-extern struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
-					    struct ceph_osdmap *map,
-					    struct ceph_messenger *msgr);
+struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
+					     struct ceph_osdmap *map);
 extern void ceph_osdmap_destroy(struct ceph_osdmap *map);
 
 /* calculate mapping of a file extent to an object */