Update Si-SR4 release notes with TransportPCE

Update Si-SR4 release notes with TransportPCE

- retrieve TransportPCE Si-SR3 parent commit hash

https://git.opendaylight.org/gerrit/gitweb?p=transportpce.git
;a=commit;h=b7c2eb307943549d5b50925f32a1fa336ef5e2ba

- use it with this oneliner script to generate release-notes section

git log --oneline 16d05e92d65efdcab2031b49cc8cba653fac8ac6..HEAD \
| grep -v Merge \
| sed 's@^\(........\)[^ ]* @* `\1 <https://git.opendaylight.org/gerrit
/q/\1>`_\n  : @'

Signed-off-by: guillaume.lambert <guillaume.lambert@orange.com>
Change-Id: I14f2a5f2c40482028cd5cbed7fd4cbbcab807ef0