lib: Add FIT payload support

* Add support for parsing and booting FIT payloads.
* Build fit loader code from depthcharge.
* Fix coding style.
* Add Kconfig option to add compiletime support for FIT.
* Add support for initrd.
* Add default compat strings
* Apply optional devicetree fixups using dt_apply_fixups

Starting at this point the CBFS payload/ can be either SELF or FIT.

Tested on Cavium SoC: Parses and loads a Linux kernel 4.16.3.
Tested on Cavium SoC: Parses and loads a Linux kernel 4.15.0.
Tested on Cavium SoC: Parses and loads a Linux kernel 4.1.52.

Change-Id: I0f27b92a5e074966f893399eb401eb97d784850d
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/25019
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
9 files changed