MFC r320296, r328173: Update dtc(1)

MFC r320296 (manu): dtc: Update to upstream 9ce35ff8

• Add "compatible with gpl dtc X.Y.Z" to version output so U-Boot doesn't complain
• Fix cross reference node

This fixes some Allwinner DTS (and probably others).

MFC r328173: dtc(1): Update to upstream ea3c233

Highlights of this update:

• /__local_fixups__ is now generated to be GPL dtc and libfdt compliant
• Compiling with -@ will now cause dtc to assign phandles to all labelled nodes
• /include/ and /incbin/ now handle absolute paths correctly
• The manpage now has information about overlays, including how to apply them and how to generate them
• Syntactic sugar for overlays is now supported, allowing an overlay DTS like:

/dts-v1/;
/plugin/;

&foo {

foo,status = "okay";

};

to generate a fragment targetting <&foo>.