MLK-21410 can: flexcan: add CAN wakeup function for MX8

MLK-21410 can: flexcan: add CAN wakeup function for MX8

This patch is to add CAN wakeup function on MX8 platforms and update the
binding file fsl-flexcan.txt.

For MX8, the function "flexcan_irq()" should not call "flexcan_exit_stop_mode()"
due to firmware(SCU) cannot make SC IPC calls from an interrupt context.
If not exit stop mode in ISR, it will continuously enter wakeup ISR for the reason
that system will respond IRQ before call CAN system resume.
To fix the issue, we can exit stop mode during noirq resume stage.

For wakeup case, it should not set pinctrl to sleep state by
pinctrl_pm_select_sleep_state.

Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>