comment fixes

hi,

see the following patch.
it seems some function names in the comment are out of sync with the reality.

YAMAMOTO Takashi

diff --git a/src/backend/executor/execProcnode.c b/src/backend/executor/execProcnode.c
index 8bdfad2..284fc6a 100644
--- a/src/backend/executor/execProcnode.c
+++ b/src/backend/executor/execProcnode.c
@@ -55,7 +55,7 @@
  *        of ExecInitNode() is a plan state tree built with the same structure
  *        as the underlying plan tree.
  *
- *      * Then when ExecRun() is called, it calls ExecutePlan() which calls
+ *      * Then when ExecutorRun() is called, it calls ExecutePlan() which calls
  *        ExecProcNode() repeatedly on the top node of the plan state tree.
  *        Each time this happens, ExecProcNode() will end up calling
  *        ExecNestLoop(), which calls ExecProcNode() on its subplans.
@@ -65,7 +65,7 @@
  *        form the tuples it returns.
  *
  *      * Eventually ExecSeqScan() stops returning tuples and the nest
- *        loop join ends.  Lastly, ExecEnd() calls ExecEndNode() which
+ *        loop join ends.  Lastly, ExecutorEnd() calls ExecEndNode() which
  *        calls ExecEndNestLoop() which in turn calls ExecEndNode() on
  *        its subplans which result in ExecEndSeqScan().
  *