imx: Use MXC_I2C_CLK in imx i2c driver

i2c didn't work on imx25 due to missing MXC_IPG_PERCLK. Now using
MXC_I2C_CLK on all imx systems using i2c.

Signed-off-by: Matthias Weisser <weisserm@arcor.de>
Acked-by: Stefano Babic <sbabic@denx.de>
9 files changed