powerpc/85xx: Add workaround for errata USB-14 (enable on P204x/P3041/P50x0)

On P204x/P304x/P50x0 Rev1.0, USB transmit will result in false internal
multi-bit ECC errors, which has impact on performance, so software should
disable all ECC reporting from USB1 and USB2.

In formal release document, the errata number should be USB14 instead of USB138.

Signed-off-by: xulei <Lei.Xu@freescale.com>
Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: xulei <B33228@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>