uboot-imx

pci: make pci_get_hose_head() available to external users

Put pci_get_hose_head() prototype in header so it is available to
external users, allowing them to find and iterate over all pci
controllers.

Signed-off-by: Stuart Yoder <stuart.yoder@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>