This updates the U-Boot which provides the host tools like mkimage to
version 2019.07.
The patches were cleaned up and it was checked if this still compiles
on Linux and FreeBSD.
CONFIG_FIT_SIGNATURE_MAX_SIZE is set to the default value.
The patch for libressl was merged upstream.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
169152c8d1