arm64: dts: ti: k3: Fix epwm_tbclk node name to generic name

The name "clock" is not allowed for nodes, use "clock-controller" to
remove the DTS check warning.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20230802174521.236255-3-afd@ti.com


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