gold linker 2.22: Unbreak it

gold linker 2.22: Unbreak it

The trick to avoid rebuilding 6 object files unnecessarily ended up making
the gold linker of binutils 2.22 stop working.  This commit takes them
off of the gold library and back to the gold program, and again to the
incremental-dump program.  Until somebody shows me the way the latter
program can use object files from the former one, we're just going to
build them twice.