serial: max3100: Get crystal frequency via device property

Get crystal frequency via device property instead of using
a platform data.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240409144721.638326-3-andriy.shevchenko@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>