boards: mimxrt: enable pps output

Enable pps output for mimxrt1050 and mimxrt1060 based boards for gptp
sample application validation.

Signed-off-by: Hake Huang <hake.huang@oss.nxp.com>
Co-authored-by: Seb Laveze <sebastien.laveze@nxp.com>
Signed-off-by: Xabier Marquiegui <xmarquiegui@ainguraiiot.com>