MSTP update - 19: added port level operational STP version

Added new port level #extended #parameter in MSTP module. The new #parameter shows #port level #operational #STP #version. When port level STP version changes to 802-1D STP the new parameter is set to true and otherwise it is set to false.

#802-1S #MSTP update 19 ...
[commit 569e029860c6521b7a4a47d886c6698ab515f7a9]