Build with lz4 cannot be forced off

Hello,

I tried to build MariaDB with lz4-devel package in the buildroot, but saying either

-DWITH_INNODB_LZ4=OFF

-DLZ4_LIBS=

-DWITH_INNODB_LZ4=OFF

-DLZ4_LIBS=%{_libdir}/liblz4.so

-DWITH_INNODB_LZ4=OFF

–

The build will either say "LZ4_LIBS set to NOTFOUND" or compile with "-DLZ4", thus atleast two parts will end up with "Requires: liblz4.so.1()"
(mariadb-rocksdb-engine and mariadb-server)

–

Fedora sources can be found - as usual - here:
https://src.fedoraproject.org/rpms/mariadb/tree/master