EARLY_BUILD macro: the -Qunused-arguments flag isn't passed anymore when
building this particular program. However, with clang 3.1 and -Werror,
such unused argument warnings are flagged as errors, causing buildkernel
to fail at this stage, due to the -nostdinc flag passed during linking.
Since the -nostdinc flag isn't actually needed, just remove it.
X-MFC-With: r236528
b6d1e7df8e