PCI: endpoint: pci-epf-vntb: Fix sparse ntb->reg build warning

  pci-epf-vntb.c:1128:33: sparse:     expected void [noderef] __iomem *base
  pci-epf-vntb.c:1128:33: sparse:     got struct epf_ntb_ctrl *reg

Add __iomem type cast in vntb_epf_peer_spad_read() and
vntb_epf_peer_spad_write().

Link: https://lore.kernel.org/r/20221102141014.1025893-8-Frank.Li@nxp.comReported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NFrank Li <frank.li@nxp.com>
Signed-off-by: NLorenzo Pieralisi <lpieralisi@kernel.org>
Acked-by: NManivannan Sadhasivam <mani@kernel.org>

drivers/pci/endpoint/functions/pci-epf-vntb.c

@@ -1121,7 +1121,7 @@ static u32 vntb_epf_spad_read(struct ntb_dev *ndev, int idx)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	int off = ntb->reg->spad_offset, ct = ntb->reg->spad_count * sizeof(u32);
 	u32 val;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
 	val = readl(base + off + ct + idx * sizeof(u32));
 	return val;
@@ -1132,7 +1132,7 @@ static int vntb_epf_spad_write(struct ntb_dev *ndev, int idx, u32 val)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset, ct = ctrl->spad_count * sizeof(u32);
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
 	writel(val, base + off + ct + idx * sizeof(u32));
 	return 0;
@@ -1143,7 +1143,7 @@ static u32 vntb_epf_peer_spad_read(struct ntb_dev *ndev, int pidx, int idx)
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 	u32 val;
 
 	val = readl(base + off + idx * sizeof(u32));
@@ -1155,7 +1155,7 @@ static int vntb_epf_peer_spad_write(struct ntb_dev *ndev, int pidx, int idx, u32
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 	struct epf_ntb_ctrl *ctrl = ntb->reg;
 	int off = ctrl->spad_offset;
-	void __iomem *base = ntb->reg;
+	void __iomem *base = (void __iomem *)ntb->reg;
 
 	writel(val, base + off + idx * sizeof(u32));
 	return 0;