realtek: clean up RTL930x timer DT node

realtek: clean up RTL930x timer DT node

The Realtek timer node for RTL930x doesn't have any child nodes, making
the use of '#address-cells' quite pointless. It is also not an interrupt
controller, meaning it makes no sense to define '#interrupt-cells'.

The I/O address for this node is also wrong, but this is hidden by the
fact that the driver associated with this node bypasses the usual DT
machinery and does it's own thing. Correct the address to have a sane
value, even though it isn't actually used.

Fixes: a75b9e3ecb61 ("realtek: Adding RTL930X sub-target")
Signed-off-by: Sander Vanheule <sander@svanheule.net>