asio coap: If LWIP IPV6 is disabled, automatically don't build asio & coap

- Removes need to manually exclude these components as shown at
  https://github.com/espressif/esp-idf/issues/3781#issuecomment-825742378

- Hide the config for these components if IPV6 is disabled

- The components are still included in the build, but with no source
  files


* Original commit: espressif/esp-idf@e305f29382

components/asio/component.mk

@@ -1,3 +1,5 @@
+ifdef CONFIG_LWIP_IPV6
+
 COMPONENT_ADD_INCLUDEDIRS := asio/asio/include port/include
 COMPONENT_PRIV_INCLUDEDIRS := private_include
 COMPONENT_SRCDIRS := asio/asio/src port/src
@@ -7,3 +9,5 @@ COMPONENT_OBJEXCLUDE := asio/asio/src/asio_ssl.o port/src/esp_asio_openssl_stubs
 endif
 
 COMPONENT_SUBMODULES += asio
+
+endif # CONFIG_LWIP_IPV6