staging: rtl8712: remove typedefs

Coding style fix.
Get rid of typedefs NDIS_802_11_RATES and NDIS_802_11_RATES_EX
Undo any casting that was done as a result of the typedef.

Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>