[Non-BE] Resolve "CR_FIX_JBM_FLUSH_OFFSET switch leftovers"

• Related issues: #855 (closed)
• Requested reviewers: @vaclav

Reason why this change is needed

There are two leftovers of switch CR_FIX_JBM_FLUSH_OFFSET in file ivas_jbm_dec.c. This switch was introduced in 337da8b1 as part of MR !1057 (merged).

Description of the change

Reintroduce and rename the switch to activate it again.

Affected operating points

• JBM to BINAURAL decoding when the flushing function is called due to a render granularity change

• Produced bitstream is BE compared to previous state (no encoder changes).

• For output difference, use BE or non-BE. Additionally, amount of difference can be presented.

Related to #855 (closed)