kernel: drm/amdkfd: Fix memory leak in kfd_mem_dmamap_userptr()

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Fix memory leak in kfdmemdmamapuserptr If the number of pages from the userptr BO differs from the SG BO then the allocated memory for the SG table doesn't get freed before returning -EINVAL, which may lead to a memor...