Improvee detection of multiple PPSi running instances

When /etc/init.d/ppsi.sh is called with the parameter 'restart', it
happens sometimes that the restarted PPSI process detects that another
one is running but it is not really the case. To  sove this problem, the
PPSI process is now  checking  few times with a delay in between before
to decide to exit.

arch-wrs/wrs-startup.c

@@ -139,11 +139,23 @@ int main(int argc, char **argv)
 
 	/* check if pid is 0 (shm not filled) or process with provided
 	 * pid does not exist (probably crashed) */
-	if ((ppsi_head->pid != 0) && (kill(ppsi_head->pid, 0) == 0)) {
-		wrs_shm_put(ppsi_head);
-		pp_printf("Fatal: There is another PPSi instance running. "
-			  "Exit...\n\n");
-		exit(1);
+	{
+		int nbTry=1;
+
+		while ( nbTry >= 0 ) {
+			if ((ppsi_head->pid != 0) && (kill(ppsi_head->pid, 0) == 0)) {
+				nbTry--;
+				sleep(1);
+			}
+			else
+				break;
+		}
+		if ( nbTry<0 ) {
+			wrs_shm_put(ppsi_head);
+			pp_printf("Fatal: There is another PPSi instance running. "
+				  "Exit...\n\n");
+			exit(1);
+		}
 	}
 
 	/* try connecting to HAL multiple times in case it's still not ready */