[regression] Assert in BASOP encoder with MASA LTV rate switching

Basic info

• Fixed point:
  • Encoder (fixed): 383e7f47 (also main but according to git bisect, this introduced it)

Bug description

Based on LTV run, there is a new LTV crash in MASA rate switching. Based on git bisect, this was introduced in MR !2326 (merged). Stack trace below

Ways to reproduce

./IVAS_cod -masa 2 ltv48_MASA2TC.met sw_13k2_512k.bin 48 ltv48_MASA2TC.wav debug.bit