freecad: don't build against qt5-webkit-devel on musl target.
freecad: don't build against qt5-webkit-devel on musl target.

workaround for https://github.com/void-linux/void-packages/issues/12595

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necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages