How to indicate both flag/phandle for same property in devicetree yaml ?

Hi Rob, Frank
 
I'm not familiar with DT yaml,
but how to enable both flag and phandle on same property ?

For example, bitclock-master can be both flag/phandle.

	// flag style.
	// This driver is provider if it has flag.
	// (No flag means consumer)
	bitclock-master;

	// phandle style.
	// specified driver is provider
	bitclock-master = <&xxxx>

I tried many yamls, but all case will be error.
How to incicate both flag/phandle in this case ?

bitclock-master:
  description: Indicates dai-link bit clock master
  $ref: /schemas/types.yaml#/definitions/phandle
  $ref: /schemas/types.yaml#/definitions/flag


Best regards
---
Kuninori Morimoto