Remove unused field "evttype".

Apparent oversight in commit 3855968.

Author: tglsfdc

src/bin/pg_dump/pg_dump.h

@@ -361,7 +361,6 @@ typedef struct _evttriggerInfo
 	char	   *evtowner;
 	char	   *evttags;
 	char	   *evtfname;
-	char		evttype;
 	char		evtenabled;
 } EventTriggerInfo;