net: mqtt: Remove internal copy of the library

Remove the internal copy of the MQTT library, that was merged internally
until upstream MQTT was available.

Signed-off-by: Robert Lubos <[email protected]>

Author: rlubos

subsys/net/lib/CMakeLists.txt

@@ -5,7 +5,6 @@
 #
 
 add_subdirectory_ifdef(CONFIG_CLOUD_API cloud)
-add_subdirectory_ifdef(CONFIG_MQTT_SOCKET_LIB mqtt_socket)
 add_subdirectory_ifdef(CONFIG_NRF_CLOUD nrf_cloud)
 add_subdirectory_ifdef(CONFIG_DOWNLOAD_CLIENT download_client)
 add_subdirectory_ifdef(CONFIG_FOTA_DOWNLOAD fota_download)

subsys/net/lib/Kconfig

@@ -5,7 +5,6 @@
 
 menu "Application protocols"
 
-rsource "mqtt_socket/Kconfig"
 rsource "nrf_cloud/Kconfig"
 rsource "download_client/Kconfig"
 rsource "fota_download/Kconfig"