staging: r8188eu: remove unused cases from GetHalDefVar8188EUsb()

GetHalDefVar8188EUsb() is never called with HAL_DEF_DRVINFO_SZ,
HAL_DEF_RA_DECISION_RATE, HAL_DEF_RA_SGI and HAL_DEF_PT_PWR_STATUS.
Remove these cases from the function.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20220128115445.6606-3-straube.linux@gmail.com


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