Bluetooth: Change LE scanning timeout macros

Define LE scanning timeout macros in jiffies just like we do for
others timeout macros.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Acked-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>