dt-bindings: vendor-prefixes: Add Sierra Wireless

Add Sierra Wireless as swir vendor prefix.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -256,6 +256,7 @@ ste	ST-Ericsson
 stericsson	ST-Ericsson
 sunchip	Shenzhen Sunchip Technology Co., Ltd
 SUNW	Sun Microsystems, Inc
+swir	Sierra Wireless
 syna	Synaptics Inc.
 synology	Synology, Inc.
 tbs	TBS Technologies