[onert/android] Update lib path (#13962)

This commit updates core library path for packaging.

ONE-DCO-1.0-Signed-off-by: Hyeongseok Oh <[email protected]>

runtime/contrib/android/api/Prebuilt.mk

@@ -18,7 +18,7 @@ include $(CLEAR_VARS)
 LOCAL_MODULE := onert_core
 PREBUILT_LIB += onert_core
 LOCAL_SRC_FILES := \
-		$(ONERT_PREBUILT_LIB_DIR)/libonert_core.so
+		$(ONERT_PREBUILT_LIB_DIR)/nnfw/libonert_core.so
 include $(PREBUILT_SHARED_LIBRARY)
 
 # backend_cpu