[master] b22da84ee build: Bump libvarnishapi soname to 3.1.0

[Poul-Henning Kamp]

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Dridi Boukelmoune writes:

>     build: Bump libvarnishapi soname to 3.1.0

I knew there were something I forgot.

Thanks for the fixes.


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Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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