schema tree CHANGE remove compiled ext defs arrays

They are now only parsed or additionally referenced
only from extension instances.
diff --git a/src/tree_schema.c b/src/tree_schema.c
index b1a662e..350201a 100644
--- a/src/tree_schema.c
+++ b/src/tree_schema.c
@@ -802,9 +802,8 @@
     }
 
     if (!mod->implemented) {
-        /* pre-compile features and extension definitions of the module */
+        /* pre-compile features of the module */
         LY_CHECK_GOTO(lys_feature_precompile(NULL, ctx, mod, mod->parsed->features, &mod->off_features), error);
-        LY_CHECK_GOTO(lys_extension_precompile(NULL, ctx, mod, mod->parsed->extensions, &mod->off_extensions), error);
     }
 
     if (latest) {
@@ -836,9 +835,8 @@
             goto error_ctx;
         }
         if (!mod->implemented) {
-            /* pre-compile features and extension definitions of the module */
+            /* pre-compile features of the submodule */
             LY_CHECK_GOTO(lys_feature_precompile(NULL, ctx, mod, inc->submodule->features, &mod->off_features), error);
-            LY_CHECK_GOTO(lys_extension_precompile(NULL, ctx, mod, mod->parsed->extensions, &mod->off_extensions), error);
         }
     }
     mod->parsed->parsing = 0;