ARM: Kirkwood: Fix Atmel vendor prefix

The documented vendor prefix for Atmel is 'atmel' not 'at' as used in
these .dts[i] files.

The i2c framework actually ignores the prefix, so making this change
does not cause compatibility issues.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lkml.kernel.org/r/1395492360-1865-4-git-send-email-andrew@lunn.ch


Signed-off-by: Jason Cooper <jason@lakedaemon.net>