x86: qemu: Make host bridge (b.d.f=0.0.0) visible

The default weak version of pci_skip_dev() in drivers/pci/pci_common.c
skips the host bridge (b.d.f = 0.0.0) which is actually the i440fx/q35
chipset for QEMU targets. Define CONFIG_PCI_CONFIG_HOST_BRIDGE to make
it visible in the PCI configuration space.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/include/configs/qemu-x86.h b/include/configs/qemu-x86.h
index 77f88d2..d01936b 100644
--- a/include/configs/qemu-x86.h
+++ b/include/configs/qemu-x86.h
@@ -29,6 +29,7 @@
 #define CONFIG_PCI_IO_PHYS		CONFIG_PCI_IO_BUS
 #define CONFIG_PCI_IO_SIZE		0xe000
 
+#define CONFIG_PCI_CONFIG_HOST_BRIDGE
 #define CONFIG_PCI_PNP
 #define CONFIG_E1000