powerpc/ifc: fix invalid CSn FTIM2.TCH setting

On some platforms, CSn FTIM2.TCH is set to zero which is invalid,
an invalid hold time makes DUT timing variances, whether it works
or not on luck.

Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
7 files changed