Migrate the include paths back to ar9300/ instead of ar9003/ .

The eventual decision here is to push the code into a contrib
dir:

sys/contrib/dev/ath/ath_hal/ar9300

.. and so it makes sense to just rename things back to how they were.

The bonus here - the branch diffs are reduced.
Reindent this code to be better BSD style'd.
Use a bitwise operator to check this flag.

clang complains on it.

Issue:	#1
Check whether AH_DEBUG is defined, rather than if it's 1 or 0.