USB: ehci: add call of free_cached_itd_list() function in disable_periodic()

Sometimes disable_periodic() stop scan_periodic before than free_cached_itd_list() was called.
In such case USB Host stacked during disconnect operation
Solution: add call of free_cached_itd_list() function in disable_periodic()

Signed-off-by: Dimitry Epshtein <dima@marvell.com>
Signed-off-by: Saeed Bishara <saeed@marvell.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>