drm/i915/gvt/scheduler: Remove unnecessary NULL checks in sr_oa_regs

The checks are misleading and not required [1].

[1] https://lkml.org/lkml/2018/3/19/1792

Addresses-Coverity-ID: 1466017
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NZhi Wang <zhi.a.wang@intel.com>

drivers/gpu/drm/i915/gvt/scheduler.c

@@ -97,7 +97,7 @@ static void sr_oa_regs(struct intel_vgpu_workload *workload,
 		i915_mmio_reg_offset(EU_PERF_CNTL6),
 	};
 
-	if (!workload || !reg_state || workload->ring_id != RCS)
+	if (workload->ring_id != RCS)
 		return;
 
 	if (save) {