PATCH: Fix shared library build for libiberty

[DJ Delorie]

> Do we want to use automake on libiberty? Every other library uses it.

Remember that libiberty does dependencies differently so that when
building in $srcdir it doesn't have to copy everything.  If automake
means a reliance on VPATH, we can't use it.  That's partly why
libiberty has its own "make maint-deps" - so that it can set up
explicit dependencies on the right files.

We also build two libraries - the regular one, and one that includes
the otherwise omitted functions (for testing).

Otherwise, I have no objection to automake, as long as it functions
the same afterwards.