HM-345: Expose actual pointing functionality in DishLN helper device.

1. What this MR does / why we need it:

• The purpose of this MR is to add actual pointing event functionality in dish leaf node helper device.

2. Make sure that you've checked the boxes below before you submit MR:

• No conflict with master branch.
• Merge Request Title appropriate.
• Unit/Integration tests added and existing test cases are passing.
• Variable and Function names state the purpose.
• There is no commented out code, print/debug statements.
• Logs are added wherever necessary.
• Exception is handled wherever required.