PCI cards might need some time after reset to respond. On some
boards (mpc5200 or mpc8260 based) the PCI bus reset is deasserted
at pci_init_board() time, so we currently can not use available
"pcidelay" option for waiting before PCI bus scan since this
waiting takes place before calling pci_init_board(). By moving
the pcidelay code to the new location using of the "pcidelay"
option is possible on mpc5200 or mpc8260 based boards, too.

Since pci_hose_scan() could be called multiple times, restrict
the function to wait only during its first call and to ignore
pcidelay for any further call (as pointed out by Matthias).

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Cc: Matthias Fuchs <matthias.fuchs@esd.eu>
Acked-by: Stefan Roese <sr@denx.de>
Acked-by: Matthias Fuchs <matthias.fuchs@esd.eu>
Tested-by: Matthias Fuchs <matthias.fuchs@esd.eu>