issue: 4039879 Reset m_rx_pkt_ready_offset after clearing RX buffer

[BasharRadya]

After clearing the RX buffer, we need to reset all related state, including m_rx_pkt_ready_offset, to ensure consistency of the state.

Change type

What kind of change does this PR introduce?

• [x] Bugfix
• [ ] Feature
• [ ] Code style update
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] CI related changes
• [ ] Documentation content changes
• [ ] Tests
• [ ] Other

Check list

• [ ] Code follows the style de facto guidelines of this project
• [ ] Comments have been inserted in hard to understand places
• [ ] Documentation has been updated (if necessary)
• [ ] Test has been added (if possible)