i2c: iop3xx: make bindings file name match the driver

If we use the "i2c-" prefix for the binding documentation file name,
then it should match the file name of the driver, if possible. It is
possible for this driver, so rename it.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/Documentation/devicetree/bindings/i2c/i2c-xscale.txt b/Documentation/devicetree/bindings/i2c/i2c-iop3xx.txt
similarity index 100%
rename from Documentation/devicetree/bindings/i2c/i2c-xscale.txt
rename to Documentation/devicetree/bindings/i2c/i2c-iop3xx.txt