drivers: gpio_dw: update to use new GPIO API

Update driver code and board files to use new GPIO configuration flags
such as GPIO_ACTIVE_LOW. Also add implementation of new port_* driver
API as well as gpio_pin_interrupt_configure function.

The interrupt triggering on both edges is a remnant from the old
Quark SE which has a customized DesignWare GPIO block. So remove
the support for both edges as the board is no longer supported.

Signed-off-by: Daniel Leung <[email protected]>

Author: dcpleung