powerpc/rman: fix RMan support for t4240 and b4860

1. Add CONFIG_SYS_DPAA_RMAN macro to t4240 and b4860.
2. Decrease RMan liodn offset number.
SET_RMAN_LIODN() is used to set liodn offset of RMan blocks 0-3.
For t4240 and b4860, RMan liodn base is assigned to 922, the original
offset number is too large that the liodn (base+offset 922+678 = 1600)
is greater than 0x500 the maximum liodn number.

Signed-off-by: Minghuan Lian <Minghuan.Lian@freescale.com>
Signed-off-by: York Sun <yorksun@freescale.com>