[Pmon docker]Add ethtool to pmon docker

[keboliu]

- What I did
Install ethtool to pmon docker.
ethtool can be an alternate way to interpret the SFP eeprom content and dump the raw data with kernel support.
1. interpret QSFP content:

    root@mtbc-sonic-03-2700:/# ethtool -m sfp1
    Identifier                                : 0x0d (QSFP+)
    Extended identifier                       : 0x00
    Extended identifier description           : 1.5W max. Power consumption
    Extended identifier description           : No CDR in TX, No CDR in RX
    Extended identifier description           : High Power Class (> 3.5 W) not enabled
    Connector                                 : 0x23 (No separable connector)
    Transceiver codes                         : 0x88 0x00 0x00 0x00 0x00 0x00 0x00 0x00
    Transceiver type                          : 40G Ethernet: 40G Base-CR4
    Transceiver type                          : 100G Ethernet: 100G Base-CR4 or 25G Base-CR CA-L
    Encoding                                  : 0x00 (unspecified)
    BR, Nominal                               : 25500Mbps
    Rate identifier                           : 0x00
    Length (SMF,km)                           : 0km
    Length (OM3 50um)                         : 0m
    Length (OM2 50um)                         : 0m
    Length (OM1 62.5um)                       : 0m
    Length (Copper or Active cable)           : 1m
    Transmitter technology                    : 0xa0 (Copper cable unequalized)
    Attenuation at 2.5GHz                     : 3db
    Attenuation at 5.0GHz                     : 5db
    Attenuation at 7.0GHz                     : 6db
    Attenuation at 12.9GHz                    : 9db
    Vendor name                               : Mellanox
    Vendor OUI                                : 00:02:c9
    Vendor PN                                 : MCP1600-E001
    Vendor rev                                : A3
    Vendor SN                                 : MT1834VS04288
    Revision Compliance                       : SFF-8636 Rev 2.0
    Module temperature                        : 0.00 degrees C / 32.00 degrees F
    Module voltage                            : 0.0000 V

2. dump SFP eeprom raw data:

root@mtbc-sonic-03-2700:/# ethtool -m sfp1 hex on
Offset          Values
------          ------
0x0000:         0d 06 06 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0010:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0020:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0030:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0040:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0050:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0060:         00 00 00 00 00 00 00 00 00 00 00 00 00 01 08 00 
0x0070:         00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0080:         0d 00 23 88 00 00 00 00 00 00 00 00 ff 00 00 00 
0x0090:         00 00 01 a0 4d 65 6c 6c 61 6e 6f 78 20 20 20 20 
0x00a0:         20 20 20 20 1f 00 02 c9 4d 43 50 31 36 30 30 2d 
0x00b0:         45 30 30 31 20 20 20 20 41 33 03 05 06 09 46 7d 
0x00c0:         0b 00 00 00 4d 54 31 38 33 34 56 53 30 34 32 38 
0x00d0:         38 20 20 20 31 38 30 38 32 34 20 20 00 00 67 69 
0x00e0:         31 39 32 32 38 32 36 37 39 33 5a 35 00 00 00 00 
0x00f0:         00 00 00 00 00 00 00 00 00 00 00 00 00 30 00 00 

3. Read SFP eeprom from certain offset:

root@mtbc-sonic-03-2700:/# ethtool -m sfp1 hex on offset 0 length 100
Offset          Values
------          ------
0x0000:         0d 06 06 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0010:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0020:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0030:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0040:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0050:         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
0x0060:         00 00 00 00 

- How I did it
install ethtool to pmon when complie the pmon docker.

- How to verify it

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