drm/radeon: update radeon_atom_is_voltage_gpio() for SI

SI uses a new atom table.  Required for DPM on SI.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/rv770_dpm.c b/drivers/gpu/drm/radeon/rv770_dpm.c
index 3c2866e..aa38764 100644
--- a/drivers/gpu/drm/radeon/rv770_dpm.c
+++ b/drivers/gpu/drm/radeon/rv770_dpm.c
@@ -2301,10 +2301,10 @@
 	pi->lmp = RV770_LMP_DFLT;
 
 	pi->voltage_control =
-		radeon_atom_is_voltage_gpio(rdev, SET_VOLTAGE_TYPE_ASIC_VDDC);
+		radeon_atom_is_voltage_gpio(rdev, SET_VOLTAGE_TYPE_ASIC_VDDC, 0);
 
 	pi->mvdd_control =
-		radeon_atom_is_voltage_gpio(rdev, SET_VOLTAGE_TYPE_ASIC_MVDDC);
+		radeon_atom_is_voltage_gpio(rdev, SET_VOLTAGE_TYPE_ASIC_MVDDC, 0);
 
 	if (atom_parse_data_header(rdev->mode_info.atom_context, index, &size,
                                    &frev, &crev, &data_offset)) {