dm: pci: Provide friendly config access functions

At present there are no PCI functions which allow access to PCI
configuration using a struct udevice. This is a sad situation for driver
model as it makes use of PCI harder. Add these functions.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2 files changed