Changes

stp: TC_tmt_loadshare*: Use new vty command 'binding-table reset'

Reset the eSLS binding table state before starting the test, to run it
with a clean state.

This test also fixes TC_unknown_client_dynamic_tmt_loadshare since it
now resets the table after connecting the 2nd dynamic ASP, which allows
re-distributing all seeds in the table into the new available set of
ASPs.

Depends: libosmo-sigtran.git Change-Id I56c34072a9ded42c13dbfc105a0ab3353ca353ec
Change-Id: I40b7724edcc06a3df641e316be4770d0e56bb72d