Put back another not-so-unnecessary #include, per report from Hiroshi Saito.

src/backend/storage/ipc/pmsignal.c

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/ipc/pmsignal.c,v 1.22 2006/07/14 14:52:22 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/ipc/pmsignal.c,v 1.23 2006/07/16 01:05:23 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -18,6 +18,7 @@
 #include <unistd.h>
 
 #include "miscadmin.h"
+#include "postmaster/postmaster.h"
 #include "storage/pmsignal.h"
 #include "storage/shmem.h"