package/binutils: install libopcodes to target/

package/binutils: install libopcodes to target/

libopcodes was installed in staging/ in commit 6a508d93610 (binutils:
Also install libopcodes in staging), but was not installed in target/

Starting with linux-5.6, perf (linux-tools) will link to libopcodes when
it is present. Since it is available in staging, the build succeeds.
However, libopcodes missing in target, perf fails at runtime:

    perf: ...libopcodes-2.33.1.so: cannot open shared object file

Install libopcodes to target as well.

Signed-off-by: Lecopzer Chen <lecopzer@gmail.com>
[yann.morin.1998@free.fr: reword commit log]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>