ANDROID: x86_64_cuttlefish_defconfig: Disable ORC unwinder.

Disable the ORC unwinder. This feature requires libelf-dev, which is
breaking some automated build systems that do not have it installed.

As we already enabled CONFIG_FRAME_POINTER, we already incurred the
performance penalty of the legacy stack unwinder, so this is pretty
much a no-op change.

Bug: 63889157
Change-Id: Ic0704ebb726c97449ed873556262cc0db3e9a6cf
Signed-off-by: Alistair Strachan <astrachan@google.com>