eolian: fix false positive use-after-free in parser

The catch here is that check_match results in a long jump under
that condition. The static analyzer doesn't know this, so declare
intent.

CID1402703

src/lib/eolian/eo_parser.c

@@ -217,6 +217,7 @@ parse_c_name(Eo_Lexer *ls)
      {
         eina_stringshare_del(cname);
         check_match(ls, ')', '(', pline, pcol);
+        return NULL; /* unreachable */
      }
    return cname;
 }