staging: wlan-ng: remove unused declarations from p80211types.h

A number of extern struct declarations in p80211types.h were causing
checkpatch warnings: "extern prototypes should be avoided in .h files"
and "function definition argument 'xxxxxx' should also have an
identifier name".

This appears to be a result of using a macro to form the declarations
and checkpatch consequently misinterpreting the declarations as
function prototypes.

On checking, the declarations have no corresponding definition in the
driver and are not used, so they are removed along with the macro used
to construct them, which is not needed elsewhere. After this change,
checkpatch reports that p80211types.h has no obvious issues.

Signed-off-by: Tim Collier <osdevtc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>