pcu: Fix PCU_Tests_SNS.TC_sns_so_bvc_reset_unknown_bvci

All BSS-originated BVC-Reset for PTP BVC must contain a Cell Identifier.
This test is not respecting that rule

libosmogb correctly detects this and discards the RESET, which is not
what is intended here:

20210305120722368 DLBSSGP ERROR BSSGP BVCI=1235 Rx RESET missing mandatory IE (gprs_bssgp.c:392)

Change-Id: I57ebfc50befc47d0690021d73b52c504f0df4f9a
Related: OS#3879
Fixes: Iea5519b453dd544c5a78b3b16ddb5132d20cf67c
1 file changed