added esp-nn again as submodule (master)

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "code/components/esp32-camera-master"]
 	path = code/components/esp32-camera-master
 	url = https://github.com/espressif/esp32-camera.git
+[submodule "code/components/esp-nn"]
+	path = code/components/esp-nn
+	url = https://github.com/espressif/esp-nn.git

code/components/esp-nn

@@ -0,0 +1 @@
+Subproject commit 6b3ef8e226a05554a6d874f6456f5ca1771c01c2