platform: mellanox: Fix order in exit flow

Fix exit flow order: call mlxplat_post_exit() after
mlxplat_i2c_main_exit() in order to unregister main i2c driver before
to "mlxplat" driver.

Fixes: 0170f616 ("platform: mellanox: Split initialization procedure")
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Michael Shych <michaelsh@nvidia.com>
Link: https://lore.kernel.org/r/20230813083735.39090-2-vadimp@nvidia.comSigned-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/x86/mlx-platform.c

@@ -6238,8 +6238,6 @@ static void mlxplat_i2c_mux_topolgy_exit(struct mlxplat_priv *priv)
 		if (priv->pdev_mux[i])
 			platform_device_unregister(priv->pdev_mux[i]);
 	}
-
-	mlxplat_post_exit();
 }
 
 static int mlxplat_i2c_main_complition_notify(void *handle, int id)
@@ -6369,6 +6367,7 @@ static void __exit mlxplat_exit(void)
 		pm_power_off = NULL;
 	mlxplat_pre_exit(priv);
 	mlxplat_i2c_main_exit(priv);
+	mlxplat_post_exit();
 }
 module_exit(mlxplat_exit);