Staging: rtl8812ae: remove undefined Kconfig macros

There are references to four undefined Kconfig macros in the code.
Remove these as the checks for them will always evaluate to false.

There are additional cleanups possible now, but I'll gladly leave those
to people that are actually familiar with the code.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>