ivas_lfe_dec fixed functions enabled in path.

[x] enables the function calls to the fixed point converted IVAS LFE decoder module which were converted earlier.
[x] Few BASOP corrections.

Pytests:
573 failed, 381 skipped and 1 passed for original inputs, +10dB scaled and -10dB scaled inputs.

MLD:
Original: 8 cases > 5
8.623086 9.196089 12.944751 22.460232 37.371952 37.676544 38.383202 39.390888

+10dB: 19 cases > 5
5.355691 5.522545 5.665263 5.665263 6.29466 6.992341 10.756404 10.756404 14.898659 16.599049 16.975687 23.381735 23.677216 27.041441 50.449856 50.464607 51.93047 51.966255 52.357201

-10dB: 7 cases > 5
8.66535 15.850086 24.997261 25.883522 26.075005 26.731424 27.376442

MLD deviation issue to be debugged.