sit: do not call ipip6devfree() from sitinitnet()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.19.222 by commit e56b65c1e74d7f706d74b51baba15187be2fb4b5, it was introduced in version v4.12 by commit cf124db566e6b036b8bcbe8decbed740bdfac8c6. For more details please see the references link.