The new iscsiuio code sets CFLAGS in configure.ac, wiping out the
environment setup by rpm. Patch that out.
Run configure for iscsiuio and open-isns from rpm, otherwise the
toplevel makefile will configure them without any arguments.
Also fix local build when iscsi-initiator-utils is installed, but having
the check to prevent overwriting configuration files during install look
in DESTDIR.
