drivers: dac: sam0: remove superfluous default n for boolean
drivers: dac: sam0: remove superfluous default n for boolean

bool symbols implicitly default to n so
there is no need to redundant those values.

Signed-off-by: Bartosz Bilas <c9544010575ed4e48ae813e3d4bf273cb2e959c4@hotmail.com>

zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr