ARM: ux500: Provide auxdata to be used as name base clock search for nmk-i2c

This patch provides a way for find_clk() to complete its name-based
searches and still find the nmk-i2c clocks. As Device Tree has a
different naming structure to that of more traditional initialisation
methods, find_clk() not succeed without these bindings.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>