* ARM AMBA Primecell PL011 serial UART

Required properties:
- compatible: must be "arm,primecell", "arm,pl011"
- reg: exactly one register range with length 0x1000
- interrupts: exactly one interrupt specifier

Optional properties:
- pinctrl:		When present, must have one state named "sleep"
			and one state named "default"
- clocks:		When present, must refer to exactly one clock named
			"apb_pclk"
- dmas:			When present, may have one or two dma channels.
			The first one must be named "rx", the second one
			must be named "tx".
- auto-poll:		Enables polling when using RX DMA.
- poll-rate-ms:		Rate at which poll occurs when auto-poll is set,
			default 100ms.
- poll-timeout-ms:	Poll timeout when auto-poll is set, default
			3000ms.

See also bindings/arm/primecell.txt
