libxshmfence: fix build with glibc 2.27

With glibc 2.27 memfd_create() is behind a _GNU_SOURCE guard, so use AC_USE_SYSTEM_EXTENSIONS to define it.

---
 .../xorg-lib/libxshmfence/extensions.patch              | 17 +++++++++++++++++
 meta/recipes-graphics/xorg-lib/libxshmfence_1.2.bb      |  2 ++
 2 files changed, 19 insertions(+)
 create mode 100644 meta/recipes-graphics/xorg-lib/libxshmfence/extensions.patch

new file mode 100644
index 00000000000..4cc9e05ab53
@@ -0,0 +1,17 @@
+With glibc 2.27 memfd_create is behind a _GNU_SOURCE guard, so call
+AC_USE_SYSTEM_EXTENSIONS to get that defined.
+
+Upstream-Status: Submitted
+Signed-off-by: Ross Burton <[email protected]>
+
+diff --git a/configure.ac b/configure.ac
+index 0c98875..ebf4dee 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -29,4 +29,6 @@ AC_CONFIG_SRCDIR([Makefile.am])
+ AC_CONFIG_HEADERS([config.h])
+ 
++AC_USE_SYSTEM_EXTENSIONS
++
+ # Initialize Automake
+ AM_INIT_AUTOMAKE([foreign dist-bzip2])

index ae34b1fe46c..1df068d1b0f 100644
@@ -13,5 +13,7 @@ DEPENDS += "virtual/libx11"
 
 BBCLASSEXTEND = "native nativesdk"
 
+SRC_URI += "file://extensions.patch"
+
 SRC_URI[md5sum] = "66662e76899112c0f99e22f2fc775a7e"
 SRC_URI[sha256sum] = "d21b2d1fd78c1efbe1f2c16dae1cb23f8fd231dcf891465b8debe636a9054b0c"

2.11.0

== Series Details ==

Series: libxshmfence: fix build with glibc 2.27
Revision: 1
URL : https://patchwork.openembedded.org/series/10752/
State : failure

== Summary ==

Thank you for submitting this patch series to OpenEmbedded Core. This is an automated response. Several tests have been executed on the proposed series by patchtest resulting in the following failures:

* Issue Upstream-Status is Submitted, but it is not mentioned where [test_upstream_status_presence_format]

  Suggested fix    Include where extensions.patch was submitted
  Current          Upstream-Status: Submitted
  Standard format  Upstream-Status: Submitted [where]

If you believe any of these test results are incorrect, please reply to the mailing list ([email protected]) raising your concerns. Otherwise we would appreciate you correcting the issues and submitting a new version of the patchset if applicable. Please ensure you add/increment the version number when sending the new version (i.e. [PATCH] -> [PATCH v2] -> [PATCH v3] -> ...).

---

Guidelines:     https://www.openembedded.org/wiki/Commit_Patch_Message_Guidelines
Test framework: http://git.yoctoproject.org/cgit/cgit.cgi/patchtest
Test suite:     http://git.yoctoproject.org/cgit/cgit.cgi/patchtest-oe