Log Message:
archivers/lz4: Remove cross-compilation patch; make different target.

The `all' target apparently includes things that aren't necessary for
the build products we expect.  Just use an empty target so that make
selects the first one in the makefile, which according to
https://github.com/lz4/lz4/issues/1240 is the reasonable choice here.

No change to the build products that are installed -- this just makes
lz4 build fewer things.