package/shairport-sync: fix build with automake 1.16.5

Fix the following build failure with convolution raised since bump of
automake to version 1.16.5 in commit
446d9f510255dda094d2ea89ad4f24a334b0ecc7 and
https://git.savannah.gnu.org/cgit/automake.git/commit/?id=f4a3a70f69e1dbccb6578f39ef47835098a04624:

configure.ac:305: error: AM_INIT_AUTOMAKE expanded multiple times
/home/giuliobenetti/autobuild/run/instance-1/output-1/host/share/aclocal-1.16/init.m4:29: AM_INIT_AUTOMAKE is expanded from...
configure.ac:6: the top level
/home/giuliobenetti/autobuild/run/instance-1/output-1/host/share/aclocal-1.16/init.m4:29: AM_INIT_AUTOMAKE is expanded from...
configure.ac:305: the top level

Fixes:
 - http://autobuild.buildroot.org/results/464148bdccb705d8992dc860262bfdeb01b7e2a1

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/shairport-sync/0002-configure.ac-fix-build-with-automake-1.16.5.patch

@@ -0,0 +1,48 @@
+From ad22edb303a470b6f9eda9fd9d3f588bb2eff8cb Mon Sep 17 00:00:00 2001
+From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+Date: Fri, 15 Oct 2021 08:02:23 +0200
+Subject: [PATCH] configure.ac: fix build with automake 1.16.5
+
+Fix the following build failure with convolution raised since automake
+1.16.5 and
+https://git.savannah.gnu.org/cgit/automake.git/commit/?id=f4a3a70f69e1dbccb6578f39ef47835098a04624:
+
+configure.ac:305: error: AM_INIT_AUTOMAKE expanded multiple times
+/home/giuliobenetti/autobuild/run/instance-1/output-1/host/share/aclocal-1.16/init.m4:29: AM_INIT_AUTOMAKE is expanded from...
+configure.ac:6: the top level
+/home/giuliobenetti/autobuild/run/instance-1/output-1/host/share/aclocal-1.16/init.m4:29: AM_INIT_AUTOMAKE is expanded from...
+configure.ac:305: the top level
+
+Fixes:
+ - http://autobuild.buildroot.org/results/464148bdccb705d8992dc860262bfdeb01b7e2a1
+
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+[Upstream status: https://github.com/mikebrady/shairport-sync/pull/1314]
+---
+ configure.ac | 3 +--
+ 1 file changed, 1 insertion(+), 2 deletions(-)
+
+diff --git a/configure.ac b/configure.ac
+index f77087c5..aa533a2d 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -3,7 +3,7 @@
+ 
+ AC_PREREQ([2.50])
+ AC_INIT([shairport-sync], [3.3.8], [4265913+mikebrady@users.noreply.github.com])
+-AM_INIT_AUTOMAKE
++AM_INIT_AUTOMAKE([subdir-objects])
+ AC_CONFIG_SRCDIR([shairport.c])
+ AC_CONFIG_HEADERS([config.h])
+ AC_PROG_RANLIB
+@@ -302,7 +302,6 @@ AM_CONDITIONAL([USE_PA], [test "x$with_pa" = "xyes"])
+ # Look for Convolution flag
+ AC_ARG_WITH(convolution, [AS_HELP_STRING([--with-convolution],[choose audio DSP convolution support])])
+ if test "x$with_convolution" = "xyes" ; then
+-  AM_INIT_AUTOMAKE([subdir-objects])
+   AC_DEFINE([CONFIG_CONVOLUTION], 1, [Include audio DSP convolution support.])
+   AC_CHECK_LIB([sndfile], [sf_open], , AC_MSG_ERROR(Convolution support requires the sndfile library -- libsndfile1-dev suggested!))
+ fi
+-- 
+2.33.0
+