kernel: net/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list()

In the Linux kernel, the following vulnerability has been resolved: net/smc: reduce rtnl pressure in smcpnetcreatepnetidslist Many syzbot reports show extreme rtnl pressure, and many of them hint that smc acquires rtnl in netns creation for no good reason 1 This patch returns early from...