Remove obsolete sudoers_cleanup() stubs.

plugins/sudoers/regress/check_symbols/check_symbols.c

@@ -114,9 +114,3 @@ main(int argc, char *argv[])
 
     exit(errors);
 }
-
-void
-sudoers_cleanup(int gotsig)
-{
-    return;
-}

plugins/sudoers/regress/iolog_path/check_iolog_path.c

@@ -202,9 +202,3 @@ void io_nextid(char *iolog_dir, char *fallback, char id[7])
 {
     memcpy(id, sessid, sizeof(sessid));
 }
-
-void
-sudoers_cleanup(int gotsig)
-{
-    return;
-}

plugins/sudoers/regress/logging/check_wrap.c

@@ -104,9 +104,3 @@ main(int argc, char *argv[])
 
     exit(0);
 }
-
-void
-sudoers_cleanup(int gotsig)
-{
-    return;
-}

plugins/sudoers/regress/parser/check_addr.c

@@ -151,13 +151,6 @@ main(int argc, char *argv[])
     exit(errors);
 }
 
-/* STUB */
-void
-sudoers_cleanup(int gotsig)
-{
-    return;
-}
-
 static int
 check_addr_printf(int msg_type, const char *fmt, ...)
 {

plugins/sudoers/regress/parser/check_fill.c

@@ -183,13 +183,6 @@ main(int argc, char *argv[])
     exit(errors);
 }
 
-/* STUB */
-void
-sudoers_cleanup(int gotsig)
-{
-    return;
-}
-
 /* STUB */
 void
 sudoerserror(const char *s)