Add network link statistics to bugreport

Instead of using the "ip link" command, this change utilizes the
"ip -s link" command to gather network link statistics, facilitating the
identification of connectivity problems.

Before:
------ NETWORK INTERFACES (ip link) ------
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode
   DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
...

After:
------ NETWORK INTERFACES (ip -s link) ------
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode
   DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    RX: bytes  packets  errors  dropped overrun mcast
    672        8        0       0       0       0
    TX: bytes  packets  errors  dropped carrier collsns
    672        8        0       0       0       0
...

Bug: 145748752
Test: manually check the bugreport generated by device
Change-Id: I299c3d7e2cbd4e99a1b058d751e5563306f7b8b1