[U-Boot] [PATCHv2] Add support for LZ4 decompression algorithm

[Julius Werner]

> You can build U-Boot with NO_SDL=1

Ah, thanks... that was the important magic flag I needed!

> Actually you should enable the option in configs/sandbox_defconfig,
> not lib/Kconfig. See the condition used by compression.c:
>
> obj-$(CONFIG_SANDBOX) += compression.o

Okay, makes sense. I looked at the wrong line in the Makefile.

> Also, for me the test fails:
>
> ./b/sandbox/u-boot -c "ut_compression"
> ...
>  testing lz4 ...
> orig_size:350
> compressed_size:276
> uncompressed_size:350
> compress does not overrun
> Failed: ret != 0
>  lz4: FAILED
> ut_compression FAILED

Huh... that's odd. When I run this now, I get:

 testing lz4 ...
        orig_size:350
        compressed_size:276
        uncompressed_size:350
        compress does not overrun
        uncompress does not overrun
 lz4: ok

And if I change a byte in the compressed test data, it fails on
memcmp() as expected. Are you sure you have no local changes or
anything (I based the patch off 1f8836396)? I don't see how this could
give different results...