dt-bindings: Add vendor prefix for PDA Precision Design Associates, Inc.

Precision Design Associates, Inc. (PDA) manufactures standard and custom
capacitive touch screens, LCD's embedded controllers and custom embedded
software. They specialize in industrial, rugged and outdoor
applications.

Website: http://www.pdaatl.com/

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1547458584-29548-2-git-send-email-eugen.hristev@microchip.com

Author: ehristev

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -289,6 +289,7 @@ ovti	OmniVision Technologies
 oxsemi	Oxford Semiconductor, Ltd.
 panasonic	Panasonic Corporation
 parade	Parade Technologies Inc.
+pda	Precision Design Associates, Inc.
 pericom	Pericom Technology Inc.
 pervasive	Pervasive Displays, Inc.
 phytec	PHYTEC Messtechnik GmbH