can: flexcan: add CAN wakeup function for i.MX8QM

can: flexcan: add CAN wakeup function for i.MX8QM

The System Controller Firmware (SCFW) is a low-level system function
which runs on a dedicated Cortex-M core to provide power, clock, and
resource management. It exists on some i.MX8 processors. e.g. i.MX8QM
(QM, QP), and i.MX8QX (QXP, DX). SCU driver manages the IPC interface
between host CPU and the SCU firmware running on M4.

For i.MX8QM, stop mode request is controlled by System Controller Unit(SCU)
firmware, this patch introduces FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW quirk
for this function.

Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20201106105627.31061-6-qiangqing.zhang@nxp.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>