dm: pci: Update a few more interfaces for const udevice *

Tidy up a few places where const * should be used.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 17051d4..7fbb4c7 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -224,7 +224,7 @@
 	return -ENOENT;
 }
 
-int fdtdec_get_pci_bar32(struct udevice *dev, struct fdt_pci_addr *addr,
+int fdtdec_get_pci_bar32(const struct udevice *dev, struct fdt_pci_addr *addr,
 			 u32 *bar)
 {
 	int barnum;