Add main, mcu, wakeup domain  uart0 pin mux into common board file and it's
reference to uart node.
Signed-off-by: Udit Kumar <u-kumar1@ti.com>
Reviewed-by: Nishanth Menon <nm@ti.com>
Link: https://lore.kernel.org/r/20230611111140.3189111-5-u-kumar1@ti.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>