Silence -Wparentheses warnings

[brad0]

/home/ports/pobj/audacity-3.5.1/audacity-Audacity-3.5.1/libraries/lib-wx-wrappers/AudacityDontAskAgainMessageDialog.cpp:57:14: warning: | has lower precedence than !=; != will be evaluated first [-Wparentheses]
   if (style | wxCENTRE != 0)
             ^~~~~~~~~~~~~~~
/home/ports/pobj/audacity-3.5.1/audacity-Audacity-3.5.1/libraries/lib-wx-wrappers/AudacityDontAskAgainMessageDialog.cpp:57:14: note: place parentheses around the '!=' expression to silence this warning
   if (style | wxCENTRE != 0)
             ^
               (            )
/home/ports/pobj/audacity-3.5.1/audacity-Audacity-3.5.1/libraries/lib-wx-wrappercd s/AudacityDontAskAgainMessageDialog.cpp:57:14: note: place parentheses around the | expression to evaluate it first
   if (style | wxCENTRE != 0)
             ^
       (               )
1 warning generated.

/home/ports/pobj/audacity-3.5.1/audacity-Audacity-3.5.1/libraries/lib-music-information-retrieval/MusicInformationRetrieval.cpp:64:17: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
   else if (bpm = GetBpmFromFilename(in.filename))
            ~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/ports/pobj/audacity-3.5.1/audacity-Audacity-3.5.1/libraries/lib-music-information-retrieval/MusicInformationRetrieval.cpp:64:17: note: place parentheses around the assignment to silence this warning
   else if (bpm = GetBpmFromFilename(in.filename))
                ^
            (                                    )
/home/ports/pobj/audacity-3.5.1/audacity-Audacity-3.5.1/libraries/lib-music-information-retrieval/MusicInformationRetrieval.cpp:64:17: note: use '==' to turn this assignment into an equality comparison
   else if (bpm = GetBpmFromFilename(in.filename))
                ^
                ==
1 warning generated.

• [X] I signed CLA
• [X] The title of the pull request describes an issue it addresses
• [X] If changes are extensive, then there is a sequence of easily reviewable commits
• [X] Each commit's message describes its purpose and effects
• [X] There are no behavior changes unnecessary for the stated purpose of the PR

Recommended:

• [X] Each commit compiles and runs on my machine without known undesirable changes of behavior

[brad0]

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