[Feature #19741] Added Init_YARP() to load from the yarp C extension

Init_YARP is called from inits.c, and it loads the YARP C extension
correctly

yarp/yarp_init.c

@@ -0,0 +1,8 @@
+#include "yarp/extension.h"
+
+void ruby_init_ext(const char *name, void (*init)(void));
+
+void
+Init_YARP() {
+    ruby_init_ext("yarp.so", Init_yarp);
+}