**- Why I did it**
We were building a custom version of Supervisor because I had added patches to prevent hangs and crashes if the system clock ever rolled backward. Those changes were merged into the upstream Supervisor repo as of version 3.4.0 (http://supervisord.org/changes.html#id9), therefore, we should be able to simply install the vanilla package via pip. This will also allow us to easily move to Python 3, as Python 3 support was added in version 4.0.0.
**- How I did it**
- Remove Makefiles and patches for building supervisor package from source
- Install Python 3 supervisor package version 4.2.1 in Buster base container
- Also install Python 3 version of supervisord-dependent-startup in Buster base container
- Debian package installed binary in `/usr/bin/`, but pip package installs in `/usr/local/bin/`, so rather than update all absolute paths, I changed all references to simply call `supervisord` and let the system PATH find the executable to prevent future need for changes just in case we ever need to switch back to build a Debian package, then we won't need to modify these again.
- Install Python 2 supervisor package >= 3.4.0 in Stretch and Jessie base containers
* buildimage: Add gearbox phy device files and a new physyncd docker to support VS gearbox phy feature
* scripts and configuration needed to support a second syncd docker (physyncd)
* physyncd supports gearbox device and phy SAI APIs and runs multiple instances of syncd, one per phy in the device
* support for VS target (sonic-sairedis vslib has been extended to support a virtual BCM81724 gearbox PHY).
HLD is located at b817a12fd8/doc/gearbox/gearbox_mgr_design.md
**- Why I did it**
This work is part of the gearbox phy joint effort between Microsoft and Broadcom, and is based
on multi-switch support in sonic-sairedis.
**- How I did it**
Overall feature was implemented across several projects. The collective pull requests (some in late stages of review at this point):
https://github.com/Azure/sonic-utilities/pull/931 - CLI (merged)
https://github.com/Azure/sonic-swss-common/pull/347 - Minor changes (merged)
https://github.com/Azure/sonic-swss/pull/1321 - gearsyncd, config parsers, changes to orchargent to create gearbox phy on supported systems
https://github.com/Azure/sonic-sairedis/pull/624 - physyncd, virtual BCM81724 gearbox phy added to vslib
**- How to verify it**
In a vslib build:
root@sonic:/home/admin# show gearbox interfaces status
PHY Id Interface MAC Lanes MAC Lane Speed PHY Lanes PHY Lane Speed Line Lanes Line Lane Speed Oper Admin
-------- ----------- --------------- ---------------- --------------- ---------------- ------------ ----------------- ------ -------
1 Ethernet48 121,122,123,124 25G 200,201,202,203 25G 204,205 50G down down
1 Ethernet49 125,126,127,128 25G 206,207,208,209 25G 210,211 50G down down
1 Ethernet50 69,70,71,72 25G 212,213,214,215 25G 216 100G down down
In addition, docker ps | grep phy should show a physyncd docker running.
Signed-off-by: syd.logan@broadcom.com