staging: ft1000-usb: use usleep_range instead of msleep

This fixes the following checkpatch.pl warning:
WARNING : msleep < 20ms can sleep for up to 20ms; see
Documentation/timers/timers-howto.txt

Signed-off-by: Catalina Mocanu <catalina.mocanu@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed