usb: xhci: fix timeout for transition from RExit to U0

usb: xhci: fix timeout for transition from RExit to U0

BugLink: https://bugs.launchpad.net/bugs/1805344
This definition is used by msecs_to_jiffies in milliseconds.
According to the comments, max rexit timeout should be 20ms.
Align with the comments to properly calculate the delay.

Verified on Sunrise Point-LP and Cannon Lake.

Cc: stable@vger.kernel.org
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit a5baeaeabcca3244782a9b6382ebab6f8a58f583)
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Acked-By: AceLan Kao <acelan.kao@canonical.com>
Acked-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>