staging/rtl8187se: Remove code without effect

The local variable AcParam is only assigned to but not read/used
afterwards, thus it and all related code can be removed.

The bFollowLegacySetting variable and check can also be removed as it is
always true.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>