Fix points_map_loader arealist parameter null value exception

/label bug

Fixed bug

Closes #15 (closed).

Required information:

• Operating system and version:
  • Ubuntu 18.04
• Autoware installation type:
  • From source
• Autoware version or commit hash
  • 1.14
• ROS distribution and version:
  • melodic
• ROS installation type:
  • deb packages via apt-get
• Package or library, if applicable:

Description of the bug

map_file -- points_map_loader arealist file cannot be loaded, program got null in the value of parameter arealist_path

Steps to reproduce the bug

1. roslaunch runtime_manager runtime_manager.launch
2. click on tab "map"
3. fill in the blank "arearlist", switch Auto update on
4. press the button Point Cloud
5. launch rviz in runtime manager
6. result point cloud map not published Provide a short, self-contained, correct example: http://sscce.org/ If you include code, do not use a screenshot.

Expected behavior

point cloud map should be published sequentially according to the current pose

Actual behavior

point cloud map not published, even one frame

Screenshots

Additional information

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Fix applied

parameter declared but not assigned in ROS pnh.param system funtion