drivers: dac: Added dac driver for samd5x

Added driver and binding file for samd5x dac peripheral, the already
implemented dac_sam0.c lacks the configuration registers for this
microcontroller family and is fixed to only have one dac channel output,
also, the code gets too bulky when adding the samd5x dac configuration
using preprocessor directives that’s why I moved the implementation to its
own file.

Added dac to the supported list of same54_xpro.yaml, fixed Kconfig.samd5x
help spacing, added board defines to test_dac.c and test it out with
twister script on board.

Signed-off-by: Rafael Aldo Hernández Luna <aldo.hernandez@daikincomfort.com>