issue: 4504533 Fix VMA_BF environment variable

[BasharRadya]

To correctly enable/disable Blueflame, we should set MLX5_SHUT_UP_BF RDMA CORE environment variable.

Description

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• Bugfix
• Feature
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• Refactoring (no functional changes, no api changes)
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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)

[BasharRadya]

@galnoam please assign peer-review

[BasharRadya]

@galnoam consider merging to the next drop? (if yes need to remove the "known issue" we added in docs )

[galnoam]

@BasharRadya, just make sure we have exported release note on the ticked, when it will mark as fixed it will be removed as part of the procedure for release notes

[BasharRadya]

@galnoam sure, release note is already in the ticket https://redmine.mellanox.com/issues/4504533 , and its already in the release notes.

[BasharRadya]

Reminder - we need to remove the known issue after we merge this
https://docs.nvidia.com/networking/display/vmav9872/known+issues#:~:text=Description%3A%20VMA_BF%20environment%20variable%20does%20not%20enable/disable%20BlueFlame%20correctly.