Cleanup CFG after profile read/instrumentation

[Jan Hubicka]

Hi,
reading profile/instrumenting breaks basic blocks and introduces fake edges.
The broken basic blocks are not re-merged until after LTO streaming that is
wasteful.  Fixed thus.

Profiledbotostrapped/regtsted ppc64-linux, comitted.

Index: tree-profile.c
===================================================================
--- tree-profile.c      (revision 202185)
+++ tree-profile.c      (working copy)
@@ -598,6 +598,8 @@ tree_profiling (void)
            }
        }
 
+      /* re-merge split blocks.  */
+      cleanup_tree_cfg ();
       update_ssa (TODO_update_ssa);
 
       rebuild_cgraph_edges ();