dt-bindings: usb: generic-ehci: document spurious-oc flag

Over-current reporting isn't supported on some platforms such as bcm63xx.
These devices will incorrectly report over-current if this flag isn't properly
activated.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20210223174455.1378-3-noltari@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>