uboot-imx

powerpc/85xx: define SRIO LIODN functions only if SRIO is defined

The P5040 does not have SRIO support, so there are no SRIO LIODNs.
Therefore, the functions that set the SRIO LIODNs should not be compiled.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>