cxl: Fix sparse warnings

Make native_irq_wait() static and use NULL rather than 0 to initialise
phb->cfg_data in cxl_pci_vphb_add() to remove sparse warnings.

Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

drivers/misc/cxl/native.c

@@ -924,7 +924,7 @@ static irqreturn_t native_irq_multiplexed(int irq, void *data)
 	return fail_psl_irq(afu, &irq_info);
 }
 
-void native_irq_wait(struct cxl_context *ctx)
+static void native_irq_wait(struct cxl_context *ctx)
 {
 	u64 dsisr;
 	int timeout = 1000;

drivers/misc/cxl/vphb.c

@@ -221,7 +221,7 @@ int cxl_pci_vphb_add(struct cxl_afu *afu)
 	/* Setup the PHB using arch provided callback */
 	phb->ops = &cxl_pcie_pci_ops;
 	phb->cfg_addr = NULL;
-	phb->cfg_data = 0;
+	phb->cfg_data = NULL;
 	phb->private_data = afu;
 	phb->controller_ops = cxl_pci_controller_ops;