Correct exit condition if sge_flag_pattern s absent

cluster/sge.enable.host.queue.sh

@@ -423,10 +423,10 @@ main() {                                                        # {{{
 		is_file_present "${file_nologin_path}" \
 			&& exit 0
 
-		## If all SGE queue(s) were manually disabled
+		## If all SGE queue(s) were manually disabled (not any flag file)
 		### Exit
 		is_file_absent "${sge_queue_flag_pattern}" \
-			|| exit 0
+			&& exit 0
 	fi
 
 	## Simple debug message with color to valid current variables