Indeterminate assertions in standard_transition_system

[zpzigi754]

With the latest uclid (f9a1ef7) , there are a few of indeterminate assertion errors in standard_transition_system.

~/trusted-abstract-platform/TrustedAbstractPlatform/standard_transition_system/proofs$ make integrity-proof
uclid --main integrity_proof ../../../Common/common-types.ucl ./../modules/ap-types.ucl  ./../modules/tap-mod.ucl  ./proof-common.ucl ./integrity-proof.ucl
Successfully parsed 5 and instantiated 1 module(s).
276 assertions passed.
0 assertions failed.
6 assertions indeterminate.
  UNDEF -> v: induction_step [Step #1] property same_tap_r_regs @ ./integrity-proof.ucl, line 162
  UNDEF -> v: induction_step [Step #1] property same_tap_e_proof_op @ ./integrity-proof.ucl, line 161
  UNDEF -> v: induction_step [Step #1] property same_tap_eid @ ./integrity-proof.ucl, line 159
  UNDEF -> v: induction_step [Step #1] property same_tap_r_eid @ ./integrity-proof.ucl, line 158
  UNDEF -> v: induction_step [Step #1] property same_tap_ter @ ./integrity-proof.ucl, line 163
  UNDEF -> v: induction_step [Step #1] property same_tap_r_proof_op @ ./integrity-proof.ucl, line 160
Finished execution for module: integrity_proof.