[non-BE] Resolve "Renderer smoke test fails in BASOP for equivalent rotation tests"

• Related issues: #2361
• Requested reviewers: @haeussler + @tritthart / @gerstacker

Reason why this change is needed

• OTR tests for REF_VEC and REF_VEC_LEV fail as described in issue

Description of the change

• Align fixed point to floating point
• Missing square root in VectorLength_fx()
• Missing ELSE in ivas_orient_trk_SetReferenceRotation_fx() overwriting value for Euler trajectories (not part of tests)
• Missing factor of 2\pi when computing pOTR->alpha
• Redundant caching of acousticFrontVector.q_fact before a call to VectorLength_fx()

Affected operating points

• Orientation tracking for IVAS_HEAD_ORIENT_TRK_REF_VEC and IVAS_HEAD_ORIENT_TRK_REF_VEC_LEV
• Number of failed testcases down from 13 to 6, remaining testcases still fail with MAX_ABS_DIFF of 4, a follow up issue is #2398
• 4 Decoder testcases are made nonBE by the fix, since now the missing square root is calculated in VectorLength_fx()

Closes #2361