CVE-2026-46027: net/smc: avoid early lgr access in smc_clc_wait_msg

In the Linux kernel, the following vulnerability has been resolved:

net/smc: avoid early lgr access in smcclcwaitmsg

A CLC decline can be received while the handshake is still in an early stage, before the connection has been associated with a link group.

The decline handling in smcclcwaitmsg() updates link-group level sync state for first-contact declines, but that state only exists after link group setup has completed. Guard the link-group update accordingly and keep the per-socket peer diagnosis handling unchanged.

This preserves the existing syncerr handling for established link-group contexts and avoids touching link-group state before it is available.