Fix CVE-2017-{8361,8363,8365}:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-8361
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-8363
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-8365

Patch copied from upstream source repository:

https://github.com/erikd/libsndfile/commit/fd0484aba8e51d16af1e3a880f9b8b857b385eb3

From fd0484aba8e51d16af1e3a880f9b8b857b385eb3 Mon Sep 17 00:00:00 2001
From: Erik de Castro Lopo <erikd@mega-nerd.com>
Date: Wed, 12 Apr 2017 19:45:30 +1000
Subject: [PATCH] FLAC: Fix a buffer read overrun

Buffer read overrun occurs when reading a FLAC file that switches
from 2 channels to one channel mid-stream. Only option is to
abort the read.

Closes: https://github.com/erikd/libsndfile/issues/230
---
 src/common.h  |  1 +
 src/flac.c    | 13 +++++++++++++
 src/sndfile.c |  1 +
 3 files changed, 15 insertions(+)

diff --git a/src/common.h b/src/common.h
index 0bd810c</td></tr></table>
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