avoid gcc warnings like:

ps/output.c:341:6: warning: the address of ‘forest_prefix’ will always evaluate as ‘true’

Index: ps/output.c
===================================================================
RCS file: /cvsroot/procps/procps/ps/output.c,v
retrieving revision 1.63
diff -u -p -r1.63 output.c
--- ps/output.c	3 May 2009 06:39:33 -0000	1.63
+++ ps/output.c	14 Nov 2010 00:24:56 -0000
@@ -338,7 +338,7 @@ static int pr_args(char *restrict const 
   unsigned flags;
   int rightward=max_rightward;
 
-  if(forest_prefix){
+  if(/*forest_prefix*/1){
     int fh = forest_helper(outbuf);
     endp += fh;
     rightward -= fh;
@@ -365,7 +365,7 @@ static int pr_comm(char *restrict const 
   unsigned flags;
   int rightward=max_rightward;
   
-  if(forest_prefix){
+  if(/*forest_prefix*/1){
     int fh = forest_helper(outbuf);
     endp += fh;
     rightward -= fh;
@@ -390,7 +390,7 @@ static int pr_fname(char *restrict const
   char *endp = outbuf;
   int rightward = max_rightward;
   
-  if(forest_prefix){
+  if(/*forest_prefix*/1){
     int fh = forest_helper(outbuf);
     endp += fh;
     rightward -= fh;