Copy the devicetree source for the A20 SoC and all existing boards
verbatim from the Linux v5.18-rc1 tag.

This commit also adds the following new board devicetrees:
 - sun7i-a20-haoyu-marsboard.dts
 - sun7i-a20-linutronix-testbox-v2.dts
 - sun7i-a20-olinuxino-lime-emmc.dts

This update includes changes to the USB PHY detection GPIO properties
which are needed to convert that driver to use the DM GPIO framework.
Signed-off-by: NSamuel Holland <samuel@sholland.org>
[Andre: fix Mele M5 U-Boot only DT]
Reviewed-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>