arm64: dts: ti: k3-am64: Merge the two main_conf nodes

There are two nodes representing the same register space, this looks to
have been created by some merge or copy/paste error. Remove the second
instance of this node and move its children into the first instance.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20230802174521.236255-2-afd@ti.com


Signed-off-by: Nishanth Menon <nm@ti.com>