ESS_butterfly: Wrap all printf / fprintf in MPI_MASTER( );

[willend]

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_Please describe what your PR is adding in terms of features or bug fixes

This minor change makes the INIT-time printf outputs from ESS_butterfly lighter by only printing from the master node.
Further, clangformat has been applied.

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Development OS / boundary conditions

Please describe what OS you developed and tested your additions on, and if any special dependencies are required:

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PR Checklist for contributing to McStas/McXtrace

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• My contribution includes patches to an existing component file

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