drm/amdgpu: cleanup unused iterator members for sdma v2.4

Signed-off-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c b/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
index 1b44d5b..fbe74a3 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
@@ -779,7 +779,7 @@ static void sdma_v2_4_vm_write_pte(struct amdgpu_ib *ib, uint64_t pe,
 	ib->ptr[ib->length_dw++] = pe;
 	ib->ptr[ib->length_dw++] = upper_32_bits(pe);
 	ib->ptr[ib->length_dw++] = ndw;
-	for (; ndw > 0; ndw -= 2, --count, pe += 8) {
+	for (; ndw > 0; ndw -= 2) {
 		ib->ptr[ib->length_dw++] = lower_32_bits(value);
 		ib->ptr[ib->length_dw++] = upper_32_bits(value);
 		value += incr;