Right now there are stubs for non CONFIG_WBRF as well as other patches are
using #ifdef CONFIG_WBRF or having their own stubs.  Like mac80211 patch
looks for #ifdef CONFIG_WBRF.

I think we should pick one or the other.

Having other subsystems #ifdef CONFIG_WBRF will make the series easier to
land through multiple trees; so I have a slight leaning in that direction.

#ifdef in C files is generally not liked because it makes build
testing harder. There are more permutations to build. It is better to use

if (IS_ENABLED(CONFIG_WBTR)) {
}

so that the code is compiled, and them throw away because
IS_ENABLED(CONFIG_WBTR) evaluates to false.

However, if the stubs are done correctly, the driver should not
care. I doubt this is used in any sort of hot path where every
instruction counts.

	Andrew