libaio: don't disable linking to the system libraries

For some reason that I don't understand (a decade-old attempt at optimisation?)
libaio disables linkage to the system libraries.  Enabling fortify means linking
to the system libraries, so remove the existing addition of -lc for x86 (the
problem also happens on at least PPC) and just link to the system libraries on
all platforms.

Also remove the sed of src/Makefile as the build not respecting LDFLAGS has been
fixed upstream.

(From OE-Core rev: f435ac9db0581d8313a38d586b00c2b3de419298)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-extended/libaio/libaio/system-linkage.patch

@@ -0,0 +1,37 @@
+From 94bba6880b1f10c6b3bf33a17ac40935d65a81ae Mon Sep 17 00:00:00 2001
+From: Ross Burton <ross.burton@intel.com>
+Date: Fri, 6 Nov 2015 15:19:46 +0000
+Subject: [PATCH] Don't remove the system libraries and startup files from
+ libaio, as in some build configurations these are required.  For example,
+ including conf/include/security_flags.inc on PPC results in:
+
+io_queue_init.os: In function `io_queue_init':
+tmp/work/ppce300c3-poky-linux/libaio/0.3.110-r0/libaio-0.3.110/src/io_queue_init.c:33:
+undefined reference to `__stack_chk_fail_local'
+
+Upstream-Status: Pending
+Signed-off-by: Ross Burton <ross.burton@intel.com>
+---
+ src/Makefile | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/Makefile b/src/Makefile
+index eadb336..56ab701 100644
+--- a/src/Makefile
++++ b/src/Makefile
+@@ -3,10 +3,10 @@ includedir=$(prefix)/include
+ libdir=$(prefix)/lib
+ 
+ CFLAGS ?= -g -fomit-frame-pointer -O2
+-CFLAGS += -nostdlib -nostartfiles -Wall -I. -fPIC
++CFLAGS += -Wall -I. -fPIC
+ SO_CFLAGS=-shared $(CFLAGS)
+ L_CFLAGS=$(CFLAGS)
+-LINK_FLAGS=
++LINK_FLAGS=$(LDFLAGS)
+ LINK_FLAGS+=$(LDFLAGS)
+ 
+ soname=libaio.so.1
+-- 
+2.1.4
+

meta/recipes-extended/libaio/libaio_0.3.110.bb

@@ -11,18 +11,13 @@ SRC_URI = "${DEBIAN_MIRROR}/main/liba/libaio/libaio_${PV}.orig.tar.gz \
            file://destdir.patch \
            file://libaio_fix_for_x32.patch \
            file://libaio_fix_for_mips_syscalls.patch \
-"
+           file://system-linkage.patch \
+           "
 
 SRC_URI[md5sum] = "2a35602e43778383e2f4907a4ca39ab8"
 SRC_URI[sha256sum] = "e019028e631725729376250e32b473012f7cb68e1f7275bfc1bbcdd0f8745f7e"
 
 EXTRA_OEMAKE =+ "prefix=${prefix} includedir=${includedir} libdir=${libdir}"
-# Need libc for stack-protector's __stack_chk_fail_local() bounce function
-LDFLAGS_append_x86 = " -lc"
-
-do_configure () {
-    sed -i 's#LINK_FLAGS=.*#LINK_FLAGS=$(LDFLAGS)#' src/Makefile
-}
 
 do_install () {
     oe_runmake install DESTDIR=${D}