drm/xe: Fix memory leak on xe_alloc_pf_queue failure

Simplify memory unwinding on error also fixing current memory
leak that can happen on error.

v2: use devm_kcalloc(Matt A)

Fixes: 3338e4f ("drm/xe: Use topology to determine page fault queue size")
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stuart Summers <stuart.summers@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240826162035.20462-1-nirmoy.das@intel.com
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>

Author: nirmoy

drivers/gpu/drm/xe/xe_gt_pagefault.c

@@ -388,20 +388,17 @@ static void pagefault_fini(void *arg)
 {
 	struct xe_gt *gt = arg;
 	struct xe_device *xe = gt_to_xe(gt);
-	int i;
 
 	if (!xe->info.has_usm)
 		return;
 
 	destroy_workqueue(gt->usm.acc_wq);
 	destroy_workqueue(gt->usm.pf_wq);
-
-	for (i = 0; i < NUM_PF_QUEUE; ++i)
-		kfree(gt->usm.pf_queue[i].data);
 }
 
 static int xe_alloc_pf_queue(struct xe_gt *gt, struct pf_queue *pf_queue)
 {
+	struct xe_device *xe = gt_to_xe(gt);
 	xe_dss_mask_t all_dss;
 	int num_dss, num_eus;
 
@@ -417,7 +414,8 @@ static int xe_alloc_pf_queue(struct xe_gt *gt, struct pf_queue *pf_queue)
 		(num_eus + XE_NUM_HW_ENGINES) * PF_MSG_LEN_DW;
 
 	pf_queue->gt = gt;
-	pf_queue->data = kcalloc(pf_queue->num_dw, sizeof(u32), GFP_KERNEL);
+	pf_queue->data = devm_kcalloc(xe->drm.dev, pf_queue->num_dw,
+				      sizeof(u32), GFP_KERNEL);
 	if (!pf_queue->data)
 		return -ENOMEM;