iommu/mediatek: Remove clk_disable in mtk_iommu_remove

After the commit b34ea31 ("iommu/mediatek: Always enable the clk on
resume"), the iommu clock is controlled by the runtime callback.
thus remove the clk control in the mtk_iommu_remove.

Otherwise, it will warning like:

echo 14018000.iommu > /sys/bus/platform/drivers/mtk-iommu/unbind

[   51.413044] ------------[ cut here ]------------
[   51.413648] vpp0_smi_iommu already disabled
[   51.414233] WARNING: CPU: 2 PID: 157 at */v5.15-rc1/kernel/mediatek/
                          drivers/clk/clk.c:952 clk_core_disable+0xb0/0xb8
[   51.417174] Hardware name: MT8195V/C(ENG) (DT)
[   51.418635] pc : clk_core_disable+0xb0/0xb8
[   51.419177] lr : clk_core_disable+0xb0/0xb8
...
[   51.429375] Call trace:
[   51.429694]  clk_core_disable+0xb0/0xb8
[   51.430193]  clk_core_disable_lock+0x24/0x40
[   51.430745]  clk_disable+0x20/0x30
[   51.431189]  mtk_iommu_remove+0x58/0x118
[   51.431705]  platform_remove+0x28/0x60
[   51.432197]  device_release_driver_internal+0x110/0x1f0
[   51.432873]  device_driver_detach+0x18/0x28
[   51.433418]  unbind_store+0xd4/0x108
[   51.433886]  drv_attr_store+0x24/0x38
[   51.434363]  sysfs_kf_write+0x40/0x58
[   51.434843]  kernfs_fop_write_iter+0x164/0x1e0

Fixes: b34ea31 ("iommu/mediatek: Always enable the clk on resume")
Reported-by: Hsin-Yi Wang <hsinyi@chromium.org>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20220503071427.2285-7-yong.wu@mediatek.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/mtk_iommu.c

@@ -957,7 +957,6 @@ static int mtk_iommu_remove(struct platform_device *pdev)
 
 	list_del(&data->list);
 
-	clk_disable_unprepare(data->bclk);
 	device_link_remove(data->smicomm_dev, &pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	devm_free_irq(&pdev->dev, data->irq, data);