[coreboot-gerrit] Change in coreboot[master]: util/cbfstool: Further reduce warnings for lz4 code

[Idwer Vollering (Code Review)]

Idwer Vollering has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/37734 )

Change subject: util/cbfstool: Further reduce warnings for lz4 code
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Patch Set 2: Code-Review+2

Tested on FreeBSD (13-CURRENT), by running 'gmake' in util/cbfstool/
Of course this is after 'menuconfig', so vb2_api.h will be present.