[Non-BE] Resolve #869: MASA pre-renderer not updating energy information in a specific case

• Related issues: #869 (closed)
• Requested reviewers: @pihlajakuja

Reason why this change is needed

MASA pre-renderer merges two MASA metadata streams. The exact method used by ivas_prerend_merge_masa_metadata depends from

• If one metadata stream is originating from an ISM input, and
• the number of directions in the metadata.

In the specific case of first input metadata originating from ISM (and the second one not originating from ISM), and both metadata streams having 1 direction, the energy after the merge is not updated. This is because the sub-routine diffuse_meta_merge_1x1 updates the energy to the first energy argument.

Description of the change

In the affected operating point, after merging the metadata, copy the updated energy information to the correct variable.

Affected operating points

• Pre-renderer when the first input metadata stream to merge is from ISM and the second not.
• This is not triggered in the current renderer application, since the stream originating from ISM always argument 2. But the bug can be triggered by a call to IVAS_REND_MergeMasaMetadata with a different order of input streams.

Related to #869 (closed)