CVE-2021-47253

In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix potential memory leak in DMUB hw_init [Why] On resume
we perform DMUB hw_init which allocates memory:
dm_resume->dm_dmub_hw_init->dc_dmub_srv_create->kzalloc That results in
memory leak in suspend/resume scenarios. [How] Allocate memory for the DC
wrapper to DMUB only if it was not allocated before. No need to reallocate
it on suspend/resume.