CVE-2025-21989

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

drm/amd/display: fix missing .is_two_pixels_per_container

Starting from 6.11, AMDGPU driver, while being loaded with amdgpu.dc=1,
due to lack of .is_two_pixels_per_container function in dce60_tg_funcs,
causes a NULL pointer dereference on PCs with old GPUs, such as R9 280X.

So this fix adds missing .is_two_pixels_per_container to dce60_tg_funcs.

(cherry picked from commit bd4b125eb949785c6f8a53b0494e32795421209d)