Even if they haven't been referenced from a .c file. Some peripherals
start their life as register definitions only, and they should still
have the documentation generated.
There _will_ be overlap in the generated lists, but doxygen doesn't seem
to mind this.
Instead of the fragile and error prone attempts to specifically
include/exclude files from doxygen by name and pattern, simply use the
already generated .d files to provide accurate and up to date lists of
all source files used.
Pros:
* Nothing left to worry about
* Much more encouraging to actually _work_ on the documentation now that
you can be sure the right docs will be generated instead of a confusing
mix.
Downsides/Upsides:
* Automatically includes all CM3/USB in each device's page _as well_ now
Downsides:
* lpc43xx still manually listed. However, completely contained in it's
own dir, so no problems
* No attempt to carry this in latex. easy, but more tempted to drop
latex support outright. (I don't think the generation there has even
worked for a while now)
* Due to the mismatch between lib directories and document roots, the
sourcelist can't be magically created per directory. There has to be
some sort of mapping between the two, so as this is doc generation only,
a static list seems sane for maintennance. (Especially compared to the
old method)
* Source list generation probably doesn't work on windows.
