Correct IVAS_cod printout help for supported MASA DTX bitrates

• Related issues: ivas-codec-pc/ivas-codec#1510 (closed)
• Requested reviewers: @pihlajakuja or anybody else from Nokia

Reason why this change is needed

• Wrong encoder printout wrt. MASA DTX.

Description of the change

• Correct the printout information.
• No compilation flag, as only the printout message is affected.

Affected operating points

• All is BE.