boards: Migrate to zephyr,mapped-partition about rp2xxx boards - remove `compatible = "fixed-partitions";` - add `compatible = "zephyr,mapped-partition";` for each partition entries - Add `ranges` for flash0 on Adafruit Metro RP2350 and WeAct RP2350B Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@gmail.com>