pinctrl: cherryview: Move custom community members to separate data struct

This is a preparatory patch for bigger clean up pending for Cherryview driver.
There is no functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>