Add the AddEmbeddingLookup method to micro_mutable_op_resolver.h (#2148)

@tensorflow/micro

Update micro_mutable_op_resolver.h

bug=fixes #2135

tensorflow/lite/micro/micro_mutable_op_resolver.h

diff --git a/tensorflow/lite/micro/micro_mutable_op_resolver.h b/tensorflow/lite/micro/micro_mutable_op_resolver.h
index ae2754b..fe4f5fb 100644
--- a/tensorflow/lite/micro/micro_mutable_op_resolver.h
+++ b/tensorflow/lite/micro/micro_mutable_op_resolver.h
@@ -224,6 +224,11 @@
     return AddBuiltin(BuiltinOperator_DIV, tflite::Register_DIV(), ParseDiv);
   }
 
+  TfLiteStatus AddEmbeddingLookup() {
+    return AddBuiltin(BuiltinOperator_EMBEDDING_LOOKUP,
+                      Register_EMBEDDING_LOOKUP(), ParseEmbeddingLookup);
+  }
+
   TfLiteStatus AddEnergy() {
     // TODO(b/286250473): change back name to "Energy" and remove namespace
     return AddCustom("SignalEnergy", tflite::tflm_signal::Register_ENERGY());