Packet: Remove extension suffix for Linux x86_64 build

* Linux x86_64 build of Python wrapper for packet library
  was originally suffixed with .cpython-38android-x86_64-linux-gnu
  to indicate that it is compiled against the Android x86_64 pyconfig.h
* However, such configuration disallow a generic Linux Python 3.8 binary
  to import bluetooth_packets_python3 module as the suffix did not match
  the expected .cpython-38-x86_64-linux-gnu
* In fact, the x86_64 config on Android is so similar to that on generic
  Linux that we can use this extension interchangeably
* Per PEP 3149, the suffix requirement is new in Python 3 and the
  interpreter will still import extensions without the suffix
* Hence, commenting out the suffix so that both Android py3-cmd and
  Linux Python3.8 can import the library without re-compilation

Bug: 143374372
Test: make, and import bluetooth_packets_python3
Change-Id: I8b0d899c630e45bf9f6398200bc1fd6105e47e3d