DT: Vendor prefixes: Add ricoh, qnap, sii and synology

The following patches make use of vendor names:
* ricoh (Ricoh Co. Ltd.);
* qnap (QNAP Systems, Inc.);
* sii (Seiko Instruments, Inc.); and
* synology (Synology, Inc.)

Add them to the vendor prefix list.
Signed-off-by: Ben Peddell <klightspeed@killerwolves.net>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -65,10 +65,12 @@ picochip	Picochip Ltd
 powervr	PowerVR (deprecated, use img)
 qca	Qualcomm Atheros, Inc.
 qcom	Qualcomm, Inc.
+qnap	QNAP Systems, Inc.
 ralink	Mediatek/Ralink Technology Corp.
 ramtron	Ramtron International
 realtek Realtek Semiconductor Corp.
 renesas	Renesas Electronics Corporation
+ricoh	Ricoh Co. Ltd.
 rockchip	Fuzhou Rockchip Electronics Co., Ltd
 samsung	Samsung Semiconductor
 sbs	Smart Battery System
@@ -76,11 +78,13 @@ schindler	Schindler
 sil	Silicon Image
 silabs	Silicon Laboratories
 simtek
+sii	Seiko Instruments, Inc.
 sirf	SiRF Technology, Inc.
 snps 	Synopsys, Inc.
 st	STMicroelectronics
 ste	ST-Ericsson
 stericsson	ST-Ericsson
+synology	Synology, Inc.
 ti	Texas Instruments
 tlm	Trusted Logic Mobility
 toshiba	Toshiba Corporation