fsl: add LAW target to fsl_pci_info structure

Add the LAW target (enum law_trgt_if) to the fsl_pci_info structure, so that
we can capture the LAW target for a given PCI or PCIE controller.  Also update
the SET_STD_PCI_INFO and SET_STD_PCIE_INFO macros to assign the
LAW_TRGT_IF_PCI[E]_x macro to the LAW target field of the structure.

This will allow future PCI[E] code to configure the LAW target automatically,
rather than requiring each board to it for each PCI controller separately.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>