OSBA decoder crash with planar SBA input

(Generic issue template)

The decoder crashes when decoding OSBA with planar FOA input.

./IVAS_cod -ism_sba 2 -1 scripts/testv/stvISM1.csv scripts/testv/stvISM2.csv 512000 48 scripts/testv/stvOSBA_2ISM_FOA48c.wav bit
./IVAS_dec BINAURAL 48 bit dec.wav

It is a similar problem as #770 (closed), which has been fixed in SBA already.