Move pci_map_physmem(), pci_unmap_physmem(), and sandbox_set_enable_pci_map() from u-boot-sandbox.h to a new file sandbox_pci.h to simplify dependencies. Fix the header order in the PCI emul file while we are here. Co-developed-by: Claude <noreply@anthropic.com> Signed-off-by: Simon Glass <sjg@chromium.org>