arm64: dts: ti: k3-j721s2: Configure pinctrl for timer IO

arm64: dts: ti: k3-j721s2: Configure pinctrl for timer IO

There are timer IO pads in the MCU domain, and in the MAIN domain. These
pads can be muxed for the related timers.

The details of the multiplexing can be found in the register
documentation and Technical Reference Manual[1].

These are similar to J721e/J7200, but have different mux capabilities.

[1] https://www.ti.com/lit/zip/spruj28

Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230531213215.602395-5-nm@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>