drm/i915/gt: Use kmemdup_array instead of kmemdup for multiple allocation

Let the kememdup_array() take care about multiplication and possible
overflows.

v2:
- Change subject
- Leave one blank line between the commit log and the tag section
- Fix code alignment issue

v3:
- Fix code alignment
- Apply the patch on a clean drm-tip

Signed-off-by: Yu Jiaoliang <yujiaoliang@vivo.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240821144036.343556-1-andi.shyti@linux.intel.com