installCDE/linux: don't try to edit/modify /etc/inetd.conf if it does not exist

Modern systems use xinetd anyway, so this code just creates useless
junk and error messages on installation.

cde/admin/IntegTools/post_install/linux/configMin.src

@@ -79,9 +79,9 @@ XCOMM
 XCOMM check for existence of /etc/inetd.conf
 XCOMM
 
-    if [ ! -f $FILE ]	# highly unlikely
+    if [ ! -f $FILE ]	# highly unlikely (in the 1990s, quite likely in 2018)
     then
-	echo "" >$FILE
+	return
     fi
 
 XCOMM
@@ -120,6 +120,11 @@ UnfixEtcInetdDotConf()
 FILE=/etc/inetd.conf
 TMPFILE=/tmp/inetd.conf
 
+    if [ ! -f $FILE ]	# highly unlikely (in the 1990s, quite likely in 2018)
+    then
+	return
+    fi
+
     awk '{if ($1 == "dtspc")
 		;
 	  else

cde/admin/IntegTools/post_install/linux/configRun.src

@@ -24,9 +24,9 @@ XCOMM
 XCOMM check for existence of /etc/inetd.conf
 XCOMM
 
-    if [ ! -f $FILE ]	# highly unlikely
+    if [ ! -f $FILE ]	# highly unlikely (in the 1990s, quite likely in 2018)
     then
-	echo "" >$FILE
+	return
     fi
 
 XCOMM
@@ -91,6 +91,11 @@ FILE=/etc/inetd.conf
 TMPFILE=/tmp/inetd.conf
 CMSD=CDE_INSTALLATION_TOP/bin/rpc.cmsd
 
+    if [ ! -f $FILE ]	# highly unlikely (in the 1990s, quite likely in 2018)
+    then
+	return
+    fi
+
     HASH first remove the CDE rpc.cmsd entry
 
     awk -v cmsd=$CMSD \

cde/admin/IntegTools/post_install/linux/configTT.src

@@ -26,9 +26,9 @@ XCOMM
 XCOMM check for existence of /etc/inetd.conf
 XCOMM
 
-    if [ ! -f $FILE ]	# highly unlikely
+    if [ ! -f $FILE ]	# highly unlikely (in the 1990s, quite likely in 2018)
     then
-	echo "" >$FILE
+	return
     fi
 
 XCOMM
@@ -64,6 +64,11 @@ FILE=/etc/inetd.conf
 TMPFILE=/tmp/inetd.conf
 TTDBSERVERD=CDE_INSTALLATION_TOP/bin/rpc.ttdbserver
 
+    if [ ! -f $FILE ]	# highly unlikely (in the 1990s, quite likely in 2018)
+    then
+	return
+    fi
+
     awk -v ttdb=$TTDBSERVERD \
 	'{if ($1 == "100083/1" && $6 == ttdb)
 		;