PVSTP feature implementation

[ph408077]

• Added new STP docker and rules to compile STP
• Added libevent required for STP

- What I did

- How I did it

- How to verify it

- Description for the changelog

- A picture of a cute animal (not mandatory but encouraged)

[ph408077]

The build failure is expected as it is not able to find stp src location. Once sonic-stp repo is merged and build retriggered, there should be no build issues.

[ FAIL LOG START ] [ target/debs/stretch/stp_1.0.0_amd64.deb ]
/bin/bash: line 9: pushd: src/sonic-stp: No such file or directory
[ FAIL LOG END ] [ target/debs/stretch/stp_1.0.0_amd64.deb ]
slave.mk:335: recipe for target 'target/debs/stretch/stp_1.0.0_amd64.deb' failed
make: *** [target/debs/stretch/stp_1.0.0_amd64.deb] Error 1
Makefile.work:190: recipe for target 'target/sonic-broadcom.bin' failed
make[1]: *** [target/sonic-broadcom.bin] Error 2

[benedikt-bartscher]

Hey there, thanks for this great PR! Is this going to be merged any time soon?

[dcantunes123]

Trying to follow this up, is there an ETA for PVST to become available?

[dotie]

@qiluo-msft @xumia @zhangyanzhao Are there any plans to approve PVSTP? This is supported in the Broadcom/Edge Core enterprise sonic builds.

[ITJamie]

@gechiang @prgeor s there anychance someone could review this / take it over? its a really important feature