drm/mediatek: Drop unnecessary check for property presence

of_property_read_u32() returns -EINVAL if a property is not present, so
the preceding check for presence with of_find_property() can be
dropped. Really, what the errno is shouldn't matter. Either the property
can be read and used or it can't and is ignored.

This is part of a larger effort to remove callers of of_find_property()
and similar functions. of_find_property() leaks the DT struct property
and data pointers which is a problem for dynamically allocated nodes
which may be freed.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20240731201407.1838385-1-robh@kernel.org/Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

drivers/gpu/drm/mediatek/mtk_disp_rdma.c

@@ -341,14 +341,11 @@ static int mtk_disp_rdma_probe(struct platform_device *pdev)
 		dev_dbg(dev, "get mediatek,gce-client-reg fail!\n");
 #endif
 
-	if (of_find_property(dev->of_node, "mediatek,rdma-fifo-size", &ret)) {
-		ret = of_property_read_u32(dev->of_node,
-					   "mediatek,rdma-fifo-size",
-					   &priv->fifo_size);
-		if (ret)
-			return dev_err_probe(dev, ret,
-					     "Failed to get rdma fifo size\n");
-	}
+	ret = of_property_read_u32(dev->of_node,
+				   "mediatek,rdma-fifo-size",
+				   &priv->fifo_size);
+	if (ret && (ret != -EINVAL))
+		return dev_err_probe(dev, ret, "Failed to get rdma fifo size\n");
 
 	/* Disable and clear pending interrupts */
 	writel(0x0, priv->regs + DISP_REG_RDMA_INT_ENABLE);