HOST_DIR/lib: symlink respectively to lib32/64

HOST_DIR/lib: symlink respectively to lib32/64

Discovered the issue on a RHEL7.4 machine where
the cmake build dynamically selected HOST_DIR/lib64
as the installation path for the lzo2 library.

Fixes failures like the following:
host-mtd
http://autobuild.buildroot.net/results/d31/d31581d2e60f35cf70312683df99c768e2ea8516/

host-squashfs
http://autobuild.buildroot.net/results/d9c/d9c95231ac774ed71580754a15ebb3b121764310/

Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>