arm64: dts: ti: k3-j784s4-mcu: Add the mcu domain watchdog instances

There are totally 2 instances of watchdog module in MCU domain.
These instances are coupled with the MCU domain R5F instances.
Disabling them as they are not used by Linux.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Link: https://lore.kernel.org/r/20231008044657.25788-6-j-keerthy@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>