libtf: Add operators size to params.

libtf.cc

@@ -264,6 +264,7 @@ extern "C" {
         libtf_resolver_init(resolver);
 
         tflite::MicroInterpreter interpreter(model, resolver, tensor_arena, tensor_arena_size, error_reporter);
+        params->operators_size = interpreter.operators_size();
 
         if (interpreter.AllocateTensors() != kTfLiteOk) {
             error_reporter->Report("AllocateTensors() failed!");

libtf.h

@@ -28,6 +28,7 @@ typedef struct libtf_parameters {
     libtf_datatype_t output_datatype;
     float output_scale;
     int output_zero_point;
+    size_t operators_size;
 } libtf_parameters_t;
 
 // Call this first to get the model parameters.