CVE-2026-46245 drm/amd/display: Fix dc_link NULL handling in HPD init

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix dclink NULL handling in HPD init amdgpudmhpdinit may see connectors without a valid dclink. The code already checks dclink for the polling decision, but later unconditionally dereferences it when setting up H...