arm64: dts: ti: k3-am64-main: add timesync router node

The Time Sync Event Router (TIMESYNC_INTRTR0) implements a set of
multiplexers to provide selection of active CPTS time sync events for
routing to CPTS capable modules.

This patch adds DT node TIMESYNC_INTRTR0 using "pinctrl-single" bindings.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com>
Link: https://lore.kernel.org/r/20211202173114.9936-1-christian.gmeiner@gmail.com