esp32: use micro-ecc from esp-idf

port/esp32/template/components/btstack/component.mk

@@ -8,6 +8,9 @@
 #
 BTSTACK_ROOT := ../../../../..
 
+# micro-ecc of WICED tree used for SECP256R1 in LE Secure Connections
+$(NAME)_COMPONENTS += micro-ecc
+
 COMPONENT_ADD_INCLUDEDIRS := \
 	${BTSTACK_ROOT}/3rd-party/bluedroid/decoder/include \
 	${BTSTACK_ROOT}/3rd-party/bluedroid/encoder/include \

src/ble/sm.c

@@ -2900,6 +2900,7 @@ static void sm_handle_random_result(uint8_t * data){
             // static version
             uECC_make_key(ec_q, ec_d);
 #endif
+#endif /* USE_MICROECC_FOR_ECDH */
 
 #ifndef WICED_VERSION
             // disable rng generator as we don't have any random bits left