appletlib: fix set-but-unused warning

When you build with FEATURE_INSTALLER disabled, you get a build
warning like so:

libbb/appletlib.c: In function 'busybox_main':
libbb/appletlib.c:691:7: warning: variable 'use_symbolic_links' set but
                                  not used [-Wunused-but-set-variable]
   int use_symbolic_links;
       ^

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
1 file changed