arm: ls102xa: enable all the snoop signal for masters.

Enable the IP feature's snoop signal to support
hardware snoop for cache coherence.

SNPCNFGCR contains the bits to drive snoop signal
for various masters.

Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>