devicetree: Add infineon to vendor-prefix.txt

Add missing vendor to vendor-prefix.txt

This commit is based on the initial work by Peter Huewe.

Cc: devicetree@vger.kernel.org
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -128,6 +128,7 @@ idt	Integrated Device Technologies, Inc.
 ifi	Ingenieurburo Fur Ic-Technologie (I/F/I)
 iom	Iomega Corporation
 img	Imagination Technologies Ltd.
+infineon Infineon Technologies
 inforce	Inforce Computing
 ingenic	Ingenic Semiconductor
 innolux	Innolux Corporation