colo-compare: compare the packet in a specified Connection

A package from pri_indev or sec_indev only belongs to a particular
Connection, so we only need to compare the package in the specified
Connection's primary_list and secondary_list, rather than for each
the whole Connection list to compare. This is time-consuming and
unnecessary.

Less checkpoint more efficiency.

Cc: Zhang Chen <zhangckid@gmail.com>
Cc: Li Zhijian <lizhijian@cn.fujitsu.com>
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>