Extended tests fail on x86_64 builders with:

rm: 'tmp-lower-bindir' is a directory
rm: 'tmp-lower-includedir' is a directory
rm: 'tmp-lower-libdir' is a directory
rm: 'tmp-lower-man1dir' is a directory
rm: 'tmp-lower-mandir' is a directory
rm: 'tmp-lower-pkgconfigdir' is a directory
rm: 'tmp-upper-bindir' is a directory
rm: 'tmp-upper-includedir' is a directory
rm: 'tmp-upper-libdir' is a directory
rm: 'tmp-upper-man1dir' is a directory
rm: 'tmp-upper-mandir' is a directory
rm: 'tmp-upper-pkgconfigdir' is a directory
make[1]: *** [Makefile:352: test-lz4-essentials] Error 1