AutotoolsPackage: remove redundant libtoolize call

This commit removes redundant calls to `libtoolize` and `aclocal`.

Some configurations, such as a Spack user using macOS with a
Homebrew-installed `libtool` added to their `packages.yaml`, have
`autoreconf` and GNU libtoolize installed as `glibtoolize`, but not
`libtoolize`. While Spack installations of `libtool` built from source
would install `glibtoolize` and symlink `libtoolize` to `glibtoolize`,
an external installation of GNU libtoolize as `glibtoolize` will not
have such a symlink, and thus the call `m.libtoolize()` will throw an
error because `libtoolize` does not exist at the path referenced by
`m.libtoolize()` (i.e.,
`self.spec['libtool'].prefix.bin.join('libtoolize')).

However, on these same systems, `autoreconf` runs correctly, and calls
`glibtoolize` instead of `libtoolize`, when appropriate. Thus,
removing the call to `libtoolize` should resolve the error mentioned
above.

The redundant call to `aclocal` is also removed in this commit because
the maintainers of GNU Automake state that "`aclocal` is expected to
disappear" and suggest that downstream users never call `aclocal`
directly -- rather, they suggest calling `autoreconf` instead.

lib/spack/spack/build_systems/autotools.py

@@ -191,10 +191,6 @@ def autoreconf(self, spec, prefix):
         tty.warn('*********************************************************')
         with working_dir(self.configure_directory):
             m = inspect.getmodule(self)
-            # This part should be redundant in principle, but
-            # won't hurt
-            m.libtoolize()
-            m.aclocal()
             # This line is what is needed most of the time
             # --install, --verbose, --force
             autoreconf_args = ['-ivf']