staging: most: dim2: remove clock speed processing from the HDM

This removes the module parameter clock_speed from the HDM code.

Instead, the platform-dependent clock speed must be delivered by the
platform driver with the help of the dim2_platform_data.clk_speed.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>