drm/i915: Fix format for perf_limit_reasons

Use hex format so that it is easier to decode.

Fixes: fe597966 ("drm/i915/debugfs: Add perf_limit_reasons in debugfs")
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230315022906.2467408-1-vinay.belgaumkar@intel.com

drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c

@@ -580,7 +580,7 @@ static bool perf_limit_reasons_eval(void *data)
 }
 
 DEFINE_SIMPLE_ATTRIBUTE(perf_limit_reasons_fops, perf_limit_reasons_get,
-			perf_limit_reasons_clear, "%llu\n");
+			perf_limit_reasons_clear, "0x%llx\n");
 
 void intel_gt_pm_debugfs_register(struct intel_gt *gt, struct dentry *root)
 {