Bitrate mismatch in initial IGF configuration for some modes

When coding e.g. SBA at 13.2 kbps WB:

./IVAS_cod -sba 3 -max_band wb 13200 16 scripts/testv/ltv16_HOA3.wav bit

the encoder outputs the following error

Internal error: IGFEncSetMode: initialization error!

This happens because for some modes there is currently a bitrate mismatch between functions getIgfPresent() and IGFEncSetMode() when doing the initial (dummy) configuration of IGF. In the specific case where the error is displayed, st->igf is set in getIgfPresent() but IGFEncSetMode() is called with a higher bitrate for which there is no IGF configuration.

Since it is not the proper configuration, this error doesn't affect the output in any way. The mismatch should still be fixed to avoid the error message.