drm/i915/gt: Fixup kerneldoc parameters

drivers/gpu/drm/i915/gt/intel_mocs.c:513: warning: Function parameter or member 'gt' not described in 'intel_mocs_init_l3cc_table'
 drivers/gpu/drm/i915/gt/intel_mocs.c:513: warning: Excess function parameter 'dev_priv' description in 'intel_mocs_init_l3cc_table'

intel_vgt_balloon/deballoon, i915_ggtt_probe_hw intel_wopcm_init_hw need
similar treatment

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190621131640.28864-2-chris@chris-wilson.co.uk