fsl_pci_init_port end-point initialization is broken

commit 70ed869e broke fsl pcie end-point initialization.
Returning 0 is not correct.  The function must return the first free
bus number for the next controller.

fsl_pci_init() must still be called and a bus allocated even if the
controller is an end-point.

Signed-off-by: Ed Swarthout <Ed.Swarthout@freescale.com>
Acked-by: Vivek Mahajan <vivek.mahajan@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>