staging: bcm: using time_after and time_before in InterfaceIdleMode.c

Used the time_after and time_before insted of comparing
the jiffies directly.This will fix the warnings and errors
found by the checkpatch.pl script.

Signed-off-by: Gokulnath Avanashilingam <Gokulnath.Avanashilingam@in.bosch.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>