buildroot

package/Makefile.in: remove $(HOST_DIR)/usr part from HOST_LDFLAGS

Now $(HOST_DIR)/lib and $(HOST_DIR)/usr/lib are the same directory, it
doesn't make sense to pass both to LDFLAGS.

Also use $(HOST_DIR)/lib instead of $(HOST_DIR)/usr/lib for the RPATH.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Reviewed-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>