ide: Fix IDE PIO size calculation

IDE PIO calculates the size wrong when passing the parameter
"ide-core.nodma=0.0" to the kernel.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>

Signed-off-by: Steven J. Hill <sjhill@mips.com>
Signed-off-by: David S. Miller <davem@davemloft.net>