GitLab

Update the libfdt source files, the upstream commit is 73e0f143b73d
("libfdt: fdt_strerror(): Fix comparison warning").

This brings us the fixes for the signed/unsigned comparison warnings,
so platforms can enable -Wsign-compare now.

Change-Id: I303d891c82ffea0acefdde27289339db5ac5a289
Signed-off-by: Andre Przywara <andre.przywara@arm.com>