systemd: fix build failure for qemux86 and qemuppc with musl

Remove the 'fstack-protector' and 'fstack-protector-strong' flags
as a workaround to fix the following error when building for qemux86
and qemuppc with musl.

  undefined reference to `__stack_chk_fail_local'

(From OE-Core rev: 4871d3c2b6dd6c07a2adcfbc9ecfb22e4afa2d0d)

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/systemd/systemd/0001-Remove-fstack-protector-flags-to-workaround-musl-bui.patch

@@ -0,0 +1,33 @@
+From e361f6b4aefae57efff7e457df8db4d1067bec23 Mon Sep 17 00:00:00 2001
+From: Chen Qi <Qi.Chen@windriver.com>
+Date: Wed, 28 Feb 2018 21:50:23 -0800
+Subject: [PATCH] Remove fstack-protector flags to workaround musl build
+
+Remove fstack-protector and fstack-protector-strong flags to fix
+the following build failure for qemux86 and qemuppc with musl.
+
+  undefined reference to `__stack_chk_fail_local'
+
+Upstream-Status: Inappropriate [OE Specific]
+
+Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
+---
+ meson.build | 2 --
+ 1 file changed, 2 deletions(-)
+
+diff --git a/meson.build b/meson.build
+index 7610ab12b..591b9cbab 100644
+--- a/meson.build
++++ b/meson.build
+@@ -329,8 +329,6 @@ foreach arg : ['-Wextra',
+                '-fdiagnostics-show-option',
+                '-fno-strict-aliasing',
+                '-fvisibility=hidden',
+-               '-fstack-protector',
+-               '-fstack-protector-strong',
+                '--param=ssp-buffer-size=4',
+               ]
+         if cc.has_argument(arg)
+-- 
+2.13.0
+

meta/recipes-core/systemd/systemd_237.bb

@@ -52,6 +52,10 @@ SRC_URI += "file://touchscreen.rules \
            "
 SRC_URI_append_qemuall = " file://0001-core-device.c-Change-the-default-device-timeout-to-2.patch"
 
+# Workaround undefined reference to `__stack_chk_fail_local' on qemux86 and qemuppc for musl
+SRC_URI_append_libc-musl_qemux86 = " file://0001-Remove-fstack-protector-flags-to-workaround-musl-bui.patch"
+SRC_URI_append_libc-musl_qemuppc = " file://0001-Remove-fstack-protector-flags-to-workaround-musl-bui.patch"
+
 PAM_PLUGINS = " \
     pam-plugin-unix \
     pam-plugin-loginuid \