security_flags.inc: disable -fstack-protector-XXX for valgrind
Valgrind (v3.11.0) expects to build with stack protection disabled
and includes -fno-stack-protector in its default CFLAGS. However, the
CFLAGS provided by OE are included on the compiler command line after
the defaults so any -fstack-protector-all / -fstack-protector-strong
option provided by security_flags.inc will cause problems.
| .../build-bcm97425vms/tmp/work/mips32el-rdk-linux/valgrind/3.11.0-r0/valgrind-3.11.0/coregrind/m_mallocfree.c:892: undefined reference to `__stack_chk_guard'
| .../build-bcm97425vms/tmp/work/mips32el-rdk-linux/valgrind/3.11.0-r0/valgrind-3.11.0/coregrind/m_mallocfree.c:947: undefined reference to `__stack_chk_fail'
Signed-off-by: Andre McCurdy <armccurdy@gmail.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
