ACPI: RIMT: Fix unused function warnings when CONFIG_IOMMU_API is disabled

When CONFIG_IOMMU_API is disabled, some functions defined outside its
conditional scope become unused, triggering compiler warnings reported
by the kernel test robot.

Move these function definitions inside the #ifdef CONFIG_IOMMU_API block
to prevent unused function warnings when the configuration is disabled.

Fixes: 8f7729552582 ("ACPI: RISC-V: Add support for RIMT")
Reported-by: kernel test robot <[e-mail]>
Closes: https://lore.kernel.org/oe-kbuild-all/[e-mail]/
Signed-off-by: Sunil V L <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/acpi/riscv/rimt.c

···
 	return 0;
 }
 
-/**
- * rimt_get_fwnode() - Retrieve fwnode associated with an RIMT node
- *
- * @node: RIMT table node to be looked-up
- *
- * Returns: fwnode_handle pointer on success, NULL on failure
- */
-static struct fwnode_handle *rimt_get_fwnode(struct acpi_rimt_node *node)
-{
-	struct fwnode_handle *fwnode = NULL;
-	struct rimt_fwnode *curr;
-
-	spin_lock(&rimt_fwnode_lock);
-	list_for_each_entry(curr, &rimt_fwnode_list, list) {
-		if (curr->rimt_node == node) {
-			fwnode = curr->fwnode;
-			break;
-		}
-	}
-	spin_unlock(&rimt_fwnode_lock);
-
-	return fwnode;
-}
-
 static acpi_status rimt_match_node_callback(struct acpi_rimt_node *node,
 					    void *context)
 {
···
 	return NULL;
 }
 
+/*
+ * RISC-V supports IOMMU as a PCI device or a platform device.
+ * When it is a platform device, there should be a namespace device as
+ * well along with RIMT. To create the link between RIMT information and
+ * the platform device, the IOMMU driver should register itself with the
+ * RIMT module. This is true for PCI based IOMMU as well.
+ */
+int rimt_iommu_register(struct device *dev)
+{
+	struct fwnode_handle *rimt_fwnode;
+	struct acpi_rimt_node *node;
+
+	node = rimt_scan_node(ACPI_RIMT_NODE_TYPE_IOMMU, dev);
+	if (!node) {
+		pr_err("Could not find IOMMU node in RIMT\n");
+		return -ENODEV;
+	}
+
+	if (dev_is_pci(dev)) {
+		rimt_fwnode = acpi_alloc_fwnode_static();
+		if (!rimt_fwnode)
+			return -ENOMEM;
+
+		rimt_fwnode->dev = dev;
+		if (!dev->fwnode)
+			dev->fwnode = rimt_fwnode;
+
+		rimt_set_fwnode(node, rimt_fwnode);
+	} else {
+		rimt_set_fwnode(node, dev->fwnode);
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_IOMMU_API
+
+/**
+ * rimt_get_fwnode() - Retrieve fwnode associated with an RIMT node
+ *
+ * @node: RIMT table node to be looked-up
+ *
+ * Returns: fwnode_handle pointer on success, NULL on failure
+ */
+static struct fwnode_handle *rimt_get_fwnode(struct acpi_rimt_node *node)
+{
+	struct fwnode_handle *fwnode = NULL;
+	struct rimt_fwnode *curr;
+
+	spin_lock(&rimt_fwnode_lock);
+	list_for_each_entry(curr, &rimt_fwnode_list, list) {
+		if (curr->rimt_node == node) {
+			fwnode = curr->fwnode;
+			break;
+		}
+	}
+	spin_unlock(&rimt_fwnode_lock);
+
+	return fwnode;
+}
+
 static bool rimt_pcie_rc_supports_ats(struct acpi_rimt_node *node)
 {
 	struct acpi_rimt_pcie_rc *pci_rc;
···
 
 	return NULL;
 }
-
-/*
- * RISC-V supports IOMMU as a PCI device or a platform device.
- * When it is a platform device, there should be a namespace device as
- * well along with RIMT. To create the link between RIMT information and
- * the platform device, the IOMMU driver should register itself with the
- * RIMT module. This is true for PCI based IOMMU as well.
- */
-int rimt_iommu_register(struct device *dev)
-{
-	struct fwnode_handle *rimt_fwnode;
-	struct acpi_rimt_node *node;
-
-	node = rimt_scan_node(ACPI_RIMT_NODE_TYPE_IOMMU, dev);
-	if (!node) {
-		pr_err("Could not find IOMMU node in RIMT\n");
-		return -ENODEV;
-	}
-
-	if (dev_is_pci(dev)) {
-		rimt_fwnode = acpi_alloc_fwnode_static();
-		if (!rimt_fwnode)
-			return -ENOMEM;
-
-		rimt_fwnode->dev = dev;
-		if (!dev->fwnode)
-			dev->fwnode = rimt_fwnode;
-
-		rimt_set_fwnode(node, rimt_fwnode);
-	} else {
-		rimt_set_fwnode(node, dev->fwnode);
-	}
-
-	return 0;
-}
-
-#ifdef CONFIG_IOMMU_API
 
 static struct acpi_rimt_node *rimt_node_map_id(struct acpi_rimt_node *node,
 					       u32 id_in, u32 *id_out,