Fix RtpStack static analysis Cppcheck - constVariable

- constVariable, shadowVariable, pointerSize
  and funcArgNamesDifferent warnings resolved
- buffer length rectified in RtpPacketTest

Bug: 260848240
Bug: 260847813
Bug: 260841034
Bug: 260842460
Test: VoLte/Video Call Test with device
      atest ImsMediaNativeTests
      Verified RTCP packets sent and received
Change-Id: I85eb96a795f2fed5167700ee440526418ac07c4b
13 files changed