dt-bindings: vendor-prefixes: Add "calaosystems" for CALAO Systems SAS
The Snowball SBC supported by arch/arm/boot/dts/ste-snowball.dts
was made by CALAO Systems and uses the "calaosystems,snowball-a9500"
compatible. Prepare for documenting the compatible by adding
"calaosystems" to the list of vendor prefixes.
Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Rob Herring <robh@kernel.org>