[patch] x86: lock bitops

I missed an obvious one! x86 CPUs are defined not to reorder stores past earlier loads, so there is no hardware memory barrier required to implement a release-consistent store (all stores are, by definition). So ditch the generic lock bitops, and implement optimised versions for x86, which

[patch] x86: lock bitops

I missed an obvious one! x86 CPUs are defined not to reorder stores past earlier loads, so there is no hardware memory barrier required to implement a release-consistent store (all stores are, by definition). So ditch the generic lock bitops, and implement optimised versions for x86, which