This should help gcc detect and use target ISA on x86_64 machines when
-march is not used on cmdline
[YOCTO #139]
(From OE-Core rev: f9e410521c92e2458ba7e2ca63d28434618b9f25)
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Cc: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>