Staging: add pata_rdc driver

This is our IDE Source code. This is base on kernel 2.6.28.  pata_rdc.h
and pata_rdc.c

From: Kevin Huang <Kevin.Huang@rdc.com.tw>
Cc: Tomy Wang <Tomy.Wang@rdc.com.tw>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>