ceph: update support for PGID64, PGPOOL3, OSDENC protocol features

Support (and require) the PGID64, PGPOOL3, and OSDENC protocol features.
These have been present in ceph.git since v0.42, Feb 2012.  Require these
features to simplify support; nobody is running older userspace.

Note that the new request and reply encoding is still not in place, so the new
code is not yet functional.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
diff --git a/include/linux/ceph/mdsmap.h b/include/linux/ceph/mdsmap.h
index cb15b5d..87ed09f 100644
--- a/include/linux/ceph/mdsmap.h
+++ b/include/linux/ceph/mdsmap.h
@@ -29,8 +29,8 @@
 
 	/* which object pools file data can be stored in */
 	int m_num_data_pg_pools;
-	u32 *m_data_pg_pools;
-	u32 m_cas_pg_pool;
+	u64 *m_data_pg_pools;
+	u64 m_cas_pg_pool;
 };
 
 static inline struct ceph_entity_addr *