The hisi_pcie_probe() function is incorrectly marked as __init, as Kconfig
tells us:
WARNING: drivers/pci/host/built-in.o(.data+0x7780): Section mismatch in reference from the variable hisi_pcie_driver to the function .init.text:hisi_pcie_probe()
If the probe for this device gets deferred past the point where __init
functions are removed, or the device is unbound and then reattached to the
driver, we branch into uninitialized memory, which is bad.
Remove the __init annotation from hisi_pcie_probe() and
hisi_add_pcie_port().