staging: r8188eu: remove HW_VAR_FWLPS_RF_ON from GetHwReg8188EU()

staging: r8188eu: remove HW_VAR_FWLPS_RF_ON from GetHwReg8188EU()

Move the functionality of the HW_VAR_FWLPS_RF_ON case in
GetHwReg8188EU() to a static function in rtw_pwrctrl.c and remove the
HW_VAR_FWLPS_RF_ON case from GetHwReg8188EU(). This is part of the
ongoing effort to get rid of the unwanted hal layer.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20220331130522.6648-5-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>