Fix some return types for SDL functions

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passed #24146
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jsdoor-freebsd

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passed #24147
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jsdoor-linux

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jsdoor-windows

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sbbs-freebsd

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sbbs-linux

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sbbs-windows

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sexpots-freebsd

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sexpots-linux

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sexpots-windows

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passed #24144
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syncdraw-freebsd

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syncdraw-linux

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syncterm-freebsd

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syncterm-linux

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passed #24143
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syncterm-windows

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