Rename static function to avoid conflicting names

Commit a4fd3aa719 moved setup_cancel_handler out of psql and
exporeted it as a global function.  While pg_dump isn't using
the header it's exported in,  having a conflicting name still
risks causing confusion when grepping the code for callsites,
so rename the static function in pg_dump to avoid this.

Author: Yugo Nagata <nagata@sraoss.co.jp>
Discussion: https://postgr.es/m/20240126094245.cf6718cc659273765f3ab69a@sraoss.co.jp

src/bin/pg_dump/parallel.c

@@ -204,7 +204,7 @@ static ParallelSlot *GetMyPSlot(ParallelState *pstate);
 static void archive_close_connection(int code, void *arg);
 static void ShutdownWorkersHard(ParallelState *pstate);
 static void WaitForTerminatingWorkers(ParallelState *pstate);
-static void setup_cancel_handler(void);
+static void set_cancel_handler(void);
 static void set_cancel_pstate(ParallelState *pstate);
 static void set_cancel_slot_archive(ParallelSlot *slot, ArchiveHandle *AH);
 static void RunWorker(ArchiveHandle *AH, ParallelSlot *slot);
@@ -550,7 +550,7 @@ sigTermHandler(SIGNAL_ARGS)
 	/*
 	 * Some platforms allow delivery of new signals to interrupt an active
 	 * signal handler.  That could muck up our attempt to send PQcancel, so
-	 * disable the signals that setup_cancel_handler enabled.
+	 * disable the signals that set_cancel_handler enabled.
 	 */
 	pqsignal(SIGINT, SIG_IGN);
 	pqsignal(SIGTERM, SIG_IGN);
@@ -605,7 +605,7 @@ sigTermHandler(SIGNAL_ARGS)
  * Enable cancel interrupt handler, if not already done.
  */
 static void
-setup_cancel_handler(void)
+set_cancel_handler(void)
 {
 	/*
 	 * When forking, signal_info.handler_set will propagate into the new
@@ -705,7 +705,7 @@ consoleHandler(DWORD dwCtrlType)
  * Enable cancel interrupt handler, if not already done.
  */
 static void
-setup_cancel_handler(void)
+set_cancel_handler(void)
 {
 	if (!signal_info.handler_set)
 	{
@@ -737,7 +737,7 @@ set_archive_cancel_info(ArchiveHandle *AH, PGconn *conn)
 	 * important that this happen at least once before we fork off any
 	 * threads.
 	 */
-	setup_cancel_handler();
+	set_cancel_handler();
 
 	/*
 	 * On Unix, we assume that storing a pointer value is atomic with respect