How to bridge Node boards

SKY-9240 supports to bridge the node boards through IPMB bus.

Bridge command and IPMB address mapping as below:

# ipmitool -t IPMB address IPMI Commands

IPMB address	IPMB address
0x88 (Node D)	0x84 (Node B)
0x86 (Node C)	0x82 (Node A)