arm64: dts: freescale: imx8mm-verdin: don't limit i2c2 max. clock

arm64: dts: freescale: imx8mm-verdin: don't limit i2c2 max. clock

Verdin I2C2 may be used to access other I2C devices apart from serving
as an HDMI DDC channel.
Thus do not limit the used I2C clock frequency to 10kHz in the module
specific device tree part.
If an overlay configures i2c2 as DDC the overlay is also responsible
to cope with an appropriate I2C clock.

Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>