build: fix several issues with building tests

• MAINTAINERCLEANFILES should not rely on conditionals that could or could not clean files.

• EXTRA_DIST should not rely on conditonals that could or could not add files to the final tarball. sources should always ship.

• CLEANFILES should not rely on conditionals as ./configure can be done in between builds leaving stray files around.

• (cosmetic) move distclean-local: target with clean-local.

• drop old ipc_sock.test, start.test and resources.test shell files.

• fix make distcheck -j:
  • stop shipping or not shipping libstat_wrapper.so. libtool will only generate the .so when installing a shared library (--enable-install-tests).
  • make libstat_wrapper a module in a similar fashion of _failure_injection.
  • build ipc_sock.test in a similar fashion as ipc.test and link as module _libstat_wrapper.la. this solves multiple issues of having the binary in the final test builddir, no need to detect if libstat_wrapper.so is installed or not and workaround libtool different linking methods for inst vs noinst libraries.

• fix ipc.test linking with GLIB that should not be dependent on HAVE_FAILURE_INJECTION.

Signed-off-by: Fabio M. Di Nitto <fdinitto@redhat.com>