drm/i915/selftests: Fix GT PM sort comparators

Compare the sampled clock values instead of their addresses. Comparing
addresses leaves the samples unsorted, preventing the code from discarding
the minimum and maximum samples.

Fixes: 1a53924 ("drm/i915/selftests: Measure CS_TIMESTAMP")
Signed-off-by: Emre Cecanpunar <emreleno@gmail.com>
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Link: https://lore.kernel.org/r/20260714220430.238433-1-emreleno@gmail.com
(cherry picked from commit 682ea2d)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Author: emomaxd

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

@@ -16,9 +16,9 @@ static int cmp_u64(const void *A, const void *B)
 {
 	const u64 *a = A, *b = B;
 
-	if (a < b)
+	if (*a < *b)
 		return -1;
-	else if (a > b)
+	else if (*a > *b)
 		return 1;
 	else
 		return 0;
@@ -28,9 +28,9 @@ static int cmp_u32(const void *A, const void *B)
 {
 	const u32 *a = A, *b = B;
 
-	if (a < b)
+	if (*a < *b)
 		return -1;
-	else if (a > b)
+	else if (*a > *b)
 		return 1;
 	else
 		return 0;