sh: Fixup r7780rp pata_platform for devres conversion.

Tidy up the R7780RP I/O mapping routines and switch the
pata_platform resources to IORESOURCE_MEM types, killing off
the useless port->addr conversion.

This fixes up R7780RP to boot after the recent devres conversion.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>