dt-bindings: usb: tps6598x: make interrupts optional

dt-bindings: usb: tps6598x: make interrupts optional

The driver can poll for interrupt status so interrupts
can be optional. It is still recommended to use the
interrupt line. Polling should only be used for debug
and prototyping.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230324133741.43408-1-rogerq@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>