Fix FTBFS with Ruby 3.x due to removed rb_set_safe_level.

In Ruby 2.7 the entire concept is deprecated and in Ruby 3.x is removed
entirely - see https://bugs.ruby-lang.org/issues/16131

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

lib/kross/ruby/rubyinterpreter.cpp

@@ -16,6 +16,8 @@
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  ***************************************************************************/
+
+#include "config.h"
 #include "rubyinterpreter.h"
 
 #include <map>
@@ -83,12 +85,14 @@ RubyInterpreter::RubyInterpreter(Kross::Api::InterpreterInfo* info): Kross::Api:
     {
         initRuby();
     }
+#ifndef HAVE_RUBY_3
     if(info->hasOption("safelevel") )
     {
         kross_rb_set_safe_level( info->getOption("safelevel")->value.toInt() );
     } else {
         kross_rb_set_safe_level(3); // if the safelevel option is undefined, set it to maximum level
     }
+#endif
 }
 
 

lib/kross/ruby/rubywrapper.c

@@ -17,8 +17,11 @@
  * Boston, MA 02110-1301, USA.
  ***************************************************************************/
 
+#include "config.h"
 #include "ruby.h"
 
 void kross_rb_set_safe_level(int safelevel) {
+#ifndef HAVE_RUBY_3
     rb_set_safe_level(safelevel);
+#endif
 }