libostree: add upstream patch to fix linking errors

Support for Avahi in libostree depends on some support functions from
libsoup.
Use its own support functions in case of libsoup is not provided.

Fixes:
  http://autobuild.buildroot.net/results/5e5441822e2a94f8de51bfa0470aced84720ce31

[Peter: enable AUTORECONF as .am file is touched]
Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libostree/0002-build-add-ostree-soup-to-build-process-when-configur.patch

@@ -0,0 +1,45 @@
+From 1cd86d4978ad32405b41f864e11ac21a2474c2f3 Mon Sep 17 00:00:00 2001
+From: Marcus Folkesson <marcus.folkesson@gmail.com>
+Date: Tue, 3 Jul 2018 10:02:46 +0200
+Subject: [PATCH] build: add ostree-soup-* to build process when configured
+ with avahi
+
+Avoid getting these link errors:
+    ./.libs/libostree-1.so: undefined reference to `soup_uri_set_path'
+    ./.libs/libostree-1.so: undefined reference to `soup_uri_new'
+    ./.libs/libostree-1.so: undefined reference to `soup_uri_free'
+    ./.libs/libostree-1.so: undefined reference to `soup_uri_set_scheme'
+    ./.libs/libostree-1.so: undefined reference to `soup_uri_to_string'
+    ./.libs/libostree-1.so: undefined reference to `soup_uri_set_host'
+    ./.libs/libostree-1.so: undefined reference to `soup_uri_set_port'
+    collect2: error: ld returned 1 exit status
+
+Reproduce with:
+    ./configure --with-avahi --without-soup
+
+Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
+---
+ Makefile-libostree.am | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/Makefile-libostree.am b/Makefile-libostree.am
+index 01a209d1..dbc9ebb8 100644
+--- a/Makefile-libostree.am
++++ b/Makefile-libostree.am
+@@ -238,6 +238,13 @@ if USE_LIBSOUP
+ libostree_1_la_SOURCES += src/libostree/ostree-fetcher-soup.c
+ libostree_1_la_CFLAGS += $(OT_INTERNAL_SOUP_CFLAGS)
+ libostree_1_la_LIBADD += $(OT_INTERNAL_SOUP_LIBS)
++else
++if USE_AVAHI
++libostree_1_la_SOURCES += src/libostree/ostree-soup-uri.h \
++	src/libostree/ostree-soup-uri.c \
++	src/libostree/ostree-soup-form.c \
++	$(NULL)
++endif
+ endif
+ endif
+ 
+-- 
+2.18.0
+

package/libostree/libostree.mk

@@ -12,6 +12,8 @@ LIBOSTREE_LICENSE = LGPL-2.0+
 LIBOSTREE_LICENSE_FILES = COPYING
 LIBOSTREE_DEPENDENCIES = e2fsprogs host-bison host-pkgconf libfuse libglib2 libgpgme xz
 LIBOSTREE_INSTALL_STAGING = YES
+# For 0002-build-add-ostree-soup-to-build-process-when-configur.patch
+LIBOSTREE_AUTORECONF = YES
 
 LIBOSTREE_CONF_OPTS += \
 	--with-gpgme-prefix=$(STAGING_DIR)/usr \