staging: r8188eu: remove RF_PATH_{C,D}

pHalData->PHYRegDef[RF_PATH_C] and pHalData->PHYRegDef[RF_PATH_D]
are initialized but not used. Remove them and remove RF_PATH_C and
RF_PATH_D from the rf_radio_path enum.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20211205171342.20551-2-straube.linux@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>