powerpc/pci: Make pcibios_make_OF_bus_map() static

Function pcibios_make_OF_bus_map() is used only in pci_32.c. So make it
static.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220706104308.5390-3-pali@kernel.org

arch/powerpc/kernel/pci_32.c

@@ -36,8 +36,6 @@ int pcibios_assign_bus_offset = 1;
 EXPORT_SYMBOL(isa_io_base);
 EXPORT_SYMBOL(pci_dram_offset);
 
-void __init pcibios_make_OF_bus_map(void);
-
 static void fixup_cpc710_pci64(struct pci_dev* dev);
 static u8* pci_to_OF_bus_map;
 
@@ -108,7 +106,7 @@ make_one_node_map(struct device_node* node, u8 pci_bus)
 	}
 }
 	
-void __init
+static void __init
 pcibios_make_OF_bus_map(void)
 {
 	int i;