Fix for high MLD cases for MASA format

[x] Scaling corrected in ivas_dirac_dec_compute_diffuse_proto.

EVS 26.444 BE test passes.
decoder pytests:
MLD scores:
Original inputs: 562 failed, 374 skipped
MLD > 10: 38
MLD > 5 : 94
MLD < 5 : 430
+10dB inputs: 562 failed, 374 skipped
MLD > 10: 150
MLD > 5 : 188
MLD < 5 : 224
-10dB inputs: 562 failed, 374 skipped
MLD > 10: 8
MLD > 5 : 45
MLD < 5 : 509

encoder pytests results:
MLD scores:
Original inputs: 562 tests:
MLD > 10: 15
MLD > 5 : 47
MLD < 5 : 500
+10dB inputs: 562 tests:
MLD > 10: 42
MLD > 5 : 133
MLD < 5 : 387
\-10dB inputs: 562 tests:
MLD > 10: 5
MLD > 5 : 21
MLD < 5 : 536