vty: add f_verify_talloc_count()

Counts talloc objects via VTY and waits for a specific object count.
Useful to test against leaks.

The intended use is to check against leakage of bsc_subscr and
gsm_subscriber_connection after each BSC_Tests.*, see patch in 'Related'
below.

Related: OS#5337
Related: I69d4c5c6f8d499bb7f0b96a48af045361433c57b (osmo-ttcn3-hacks)
Change-Id: Iafe720a4931270e868f40c4f623d10bb9c14dc80
1 file changed