The PCI bus number is printed as hex number (base = 16) but without the "0x"
prefix in the syslog, as can be seen here:
  pci_bus 0000:00: root bus resource [io  0x0000-0xffff]
  pci_bus 0000:00: root bus resource [mem 0xfffffffff8000000-0xfffffffff87fffff]
  pci_bus 0000:00: root bus resource [bus 00-07]

Add the SPECIAL flag to the printk format to add the 0x prefix.

Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index a3790c43a0ab..f52fc95981b5 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1088,7 +1088,7 @@ char *resource_string(char *buf, char *end, struct resource *res,
 		.base = 16,
 		.field_width = 2,
 		.precision = -1,
-		.flags = SMALL | ZEROPAD,
+		.flags = SPECIAL | SMALL | ZEROPAD,
 	};
 	static const struct printf_spec str_spec = {
 		.field_width = -1,