edison: ads7951: Correct bus speed for ADC chip
edison: ads7951: Correct bus speed for ADC chip

It appears that on higher speed one bit of word has been swallowed or so.
The root cause is not known and for time being the mitigation is to decrease
bus speed to 10MHz.

Signed-off-by: Andy Shevchenko <74f0c009df510614346aa771cd21959b78cdb413@linux.intel.com>

westeri/meta-acpi,westeri/meta-acpi