drm/radeon/kms/combios: fix dynamic allocation of PM clock modes

I missed the combios path when I updated the atombios pm code.

Reported by amarsh04 on IRC.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_combios.c b/drivers/gpu/drm/radeon/radeon_combios.c
index 8bf83c4..81fc100 100644
--- a/drivers/gpu/drm/radeon/radeon_combios.c
+++ b/drivers/gpu/drm/radeon/radeon_combios.c
@@ -2563,14 +2563,17 @@
 
 	/* allocate 2 power states */
 	rdev->pm.power_state = kzalloc(sizeof(struct radeon_power_state) * 2, GFP_KERNEL);
-	if (!rdev->pm.power_state) {
-		rdev->pm.default_power_state_index = state_index;
-		rdev->pm.num_power_states = 0;
-
-		rdev->pm.current_power_state_index = rdev->pm.default_power_state_index;
-		rdev->pm.current_clock_mode_index = 0;
-		return;
-	}
+	if (rdev->pm.power_state) {
+		/* allocate 1 clock mode per state */
+		rdev->pm.power_state[0].clock_info =
+			kzalloc(sizeof(struct radeon_pm_clock_info) * 1, GFP_KERNEL);
+		rdev->pm.power_state[1].clock_info =
+			kzalloc(sizeof(struct radeon_pm_clock_info) * 1, GFP_KERNEL);
+		if (!rdev->pm.power_state[0].clock_info ||
+		    !rdev->pm.power_state[1].clock_info)
+			goto pm_failed;
+	} else
+		goto pm_failed;
 
 	/* check for a thermal chip */
 	offset = combios_get_table_offset(dev, COMBIOS_OVERDRIVE_INFO_TABLE);
@@ -2735,6 +2738,14 @@
 
 	rdev->pm.current_power_state_index = rdev->pm.default_power_state_index;
 	rdev->pm.current_clock_mode_index = 0;
+	return;
+
+pm_failed:
+	rdev->pm.default_power_state_index = state_index;
+	rdev->pm.num_power_states = 0;
+
+	rdev->pm.current_power_state_index = rdev->pm.default_power_state_index;
+	rdev->pm.current_clock_mode_index = 0;
 }
 
 void radeon_external_tmds_setup(struct drm_encoder *encoder)